moral can be, illegal clearly no.
Anyway i don’t understand why people have problems with that. If i make a game, you buy it, make whatever with the game for personal use. and thank for buy it!
and of course if you break the contract is supposed you must stop using it, and if you break the EPIC contract eg you are not allowing (its illegal) distribuited anything made with unreal engine since you only can redistribuited under his conditions, but… again if you continue using its for personal use there is no law which make that illegal, for denounce the company still must wait you to release or distribuited, sell or something with a law for forbiden it.