"Why does the fact nothing on this show makes any sense (in its own world or not) not matter to anyone?"
For the same reason that some people (myself included) enjoy Mamma Mia. It's one hellava lotta fun, so we overlook its shortcomings.
There's more, but since Tink already gave another good reason, I'll leave it at that...
"Are you calling me a procrastibator?" Hunter, [title of show]
"Guess who's gonna get blamed for the war in Europe?" Eugene, Brighton Beach Memoirs