Yes you can infringe copyright if you want to, you can also run red lights if you want to, and hope no-one reports you.
You've just got to be aware that you are infringing copyright and the owner does have the right to sue you for it.
Usually they won't sue you off the bat -- they'll ask you nicely to stop, and if you don't then they'll sue you.
If you're lucky, they won't even do that, they might just ignore you, or not even know about you, but they can threaten you at any time.
I obviously don't encourage this -- but if you're game you can always make such an infringing game anonymously and distribute it using torrents so that you can't be stopped... but be aware that you are violating copyright.
It is very sad to see fan games get shut down -- For example a Kings Quest fangame worked for years after getting official permission to make it, but then was shut down when the parent company changed hands... Eventually, with enough fan support, they re-gained permission to continue work, but it shows that playing in this legal grey area is dangerous.
I'm ok with getting a cease and desist warning, but what I'm wondering is are we garunteed to get that warning before they sue us? Has there ever been a case where someone who is making a game for the same purposes as I am was never even given that warning but was sued right away?