For simple puzzle/card games: there is almost certainly a FOSS alternative that’s better. Those games are so stupidly easy to make people do it as a hobby.

So … why would anyone pay for a version that’s riddled with ads, micro transactions, and visual/gameplay elements specifically designed to be addictive? Those are bad things. Particularly when most of the “paid” version’s code is likely copy and pasted from FOSS projects by someone looking to make some easy money.