pong

no you can't

Spacechem.

There are tons of games that either lack a monetary system or that have money but no trading system. (Examples of the latter include Rogue, where money serves only as a measure of score, and Super Mario Bros., where coins exist only for the "100 coins = 1-up" mechanic.)

Now, if you are looking at games where you might expect a monetary system to exist, but it doesn't, there are a few I can think of:
Zelda 2
Quest 64
Hybrid Heaven

Independence War 2 lets you trade commodities for ship systems / weapons / ammo, and you can manufacture some ammo (and a few other things, I think), but there isn't an actual currency or specific collected resource. The trades themselves are somewhat random, in that there aren't any fixed trades such as 4x Ersatz Coffee can always be traded for 1x Quad Light PBC.

Yup, currency free just supplies you find...

Leisure Suit Larry. Definitely 1 and 2, quite likely others in the series as well. Too long since I last played them.

Eye of the Beholder games.
Dungeon Hack.
Arc the Lad I.

Also, Dungeon Master. Coins exist, but they function as puzzle items, so I would argue it doesn't count as a monetary system.

Dungeon Master 2, on the other hand, does have a monetary system.

I don't quite understand the point of this thread. Is it some kind of "games with no capitalistic agenda"-list or what?

That said, The 7th Guest didn't have a monetary system, so I think it qualifies as a commie game.

Battle Realms, only water and rice!

Like heroine from Racketeer says: "Capitalism Ho!"

Btw that Racketeer game is exactly the opposite of what OP asks about. In this game you try your best to get maximum money out of adventurers, guild masters and other random people, it is a whole art of how to sell some rotten fish for 260% of its normal price XD

I think someone needs to make thread "Games where in-game currency is actually useful", as in most games you end up with millions upon millions of gold and nothing interesting to buy.

Path of Exile has no monetary system, the game's currency is valuable items. I think it's the only MMO of its kind.

Later posts of the OP have clarified what he meant. He didn't have in mind game genres with gameplay where currencies don't make sense (adv, etc), but genres where money or gold is most often used as a measure or exchange tool.

I concur with the feeling that almost all games have this underlying "capitalistic structure", just because it's our culture and we tend to repeat the forms we are familiar with. In some cases it annoys me, because it sets limits to imagination (alien societies), to understanding (real life exotic societies) and to gaming itself (although to a lesser extent). But this "capitalistic structure" isn't defined by money itself.

For instance you have action games without money where you still accumulate points to "invest" into better means to accumulate points, in order to "invest" them into faster tools of accumulation, etc... Your character, or his gun (and its upgrades) are a capitalistic endeavour without banknotes. Or you can have exotic societies that play like lazy re-skins of our own, with salaries, guilds, careers, or a purpose of accumulation and maximisation of production, any of which could have been absent from their historical realities. Pet peeves of mine include : native american societies managed like european capitalist companies, pirate games with monthly salaries for the crew (sid meier got that right, btw), etc. It's a waste of opportunity to simulate and explore actual alternative, unfamiliar systems, as we end up with perpetual mirrors instead.

It may be what the OP has in mind somehow. Games that offer more original structures, and escape our so-obvious-that-we-cannoit-think-outside-of-them exchange or progression systems.

I'll just give a weird exemple : I was following the development of a (now vaporware) alien invasion shooter, a side scrolling shoot them up where you got to pilot a huge alien mothership and fight through waves of human armies (helicopters, tanks, etc). Basically, an ID4 where you played the invaders. Of course, it involved progressive upgrades for your mothereship, better lasers, better shields, etc, and these upgrades were unlocked by the amount of human forces you had destroyed. However, this amount was tracked by a number with a dollar sign on your alien interface. It was as if the extra-terrestrials were being paid (in dollars) for the amount of destruction they managed to do, and used these monetary rewards to buy better weapons. I nitpicked that this felt annoyingly non-alien, and that simply having a different unit for this amount would have kept the principle more abstract, less out-of-place. The devs' rationale was that players immediately understand what's going on when they see dollar signs, they immediately grasp that they are accumulating a currency for upgrades. So, there, immersion versus ergonomy (or immediate readability).

Now, question. Would this difference ($ becoming * or whatever) have changed anything ? If these were stroglumf force waves instead of dollar coins, would the game fit the OP's criterias ? Would it be relevant to what he meant by "without a monetary system" ? The structure would have been the same, and it would still be a currency (though you could rationalize it in many different ways). But the thing is, it would have been apparently prohibitively unfamiliar to the player (for the sort of simple basic shooter that was meant), because not having a dollar or a gold coin, or not thinking in terms of monetary earnings and trades, is too original for us.

In my eyes, that's a limitation (in this case, as immersion-breaking as ID4's virus-vulnerable alien computers). But it illustrates how often games fall back into our familiar symbols and systems of exchanges. So, listing games that break this mould is not entirely uninteresting. But again, I'm not sure of the relevancy of the choice of unit, as opposed to actual gameplay structures.