I had a chance to get in on a slice of behind home plate season tickets, and I turned them down because I was a wee bit broke at the time. I "knew" I could sell them all for a profit - a belief that might not have turned out to be true given the recent performance of my local sports franchise - but figured someone who might want to actually attend/pay for all (most) of the games should join the club.
Years ago, a friend of mine who had a slice of season tickets which weren't behind home plate, but were pretty good, explained it this way. However the tickets were allocated in their season ticket club, he made it his priority to make sure to get a few of the "special nights." Home opener, firework night, that sort of thing. He explained that there were enough rich people out there who would basically pay anything for the "best" seats they could get their hands on for such events, and he could fund the rest of his games by selling those tickets.
But, yes, empty seats behind home plate look pretty stupid on the teevee. They'd better figure that one out.
