The stay at home mentality isn't really a notion gamers are unfamiliar with. Quite frankly, a lot of the time, outside is a bit too much for the average gamer to put up with. Not only are people literally everywhere but they also want to engage in conversation, physical interaction and even prejudice of your very appearance.
Nope, nope, do not want. Categorically not. 100% not happy with what is being asked, and there are plenty of worlds, characters and other things I'd rather be doing.
So, if an enforced way of life is to occur, every member of the human race needs something to do in order to stave off 'cabin fever'.
We've all seen the movies and they can end pretty badly for the characters, so the last thing anyone needs is to be isolated indoors with nothing to do.
Hell, we might all become chess masters and finally defeat the Russian supercomputer that has oppressed the world's greatest players for so long, but if not, at least you'll have some alternatives.