Why do TV stations double-up the same half-hour sitcoms in hour blocks so often and at times even string several of the the same sitcoms together into "marathons"? Obviosuly, Nick at Nite and TV Land do this. But I've noticed this type of scheduling occurs on local TV stations, as well. A New York City station airs back-to-back episodes of "The King of Queens," for instance. They claim this benefits viewers because they get a double dose of their favorite shows or whatever. But does this practice in any way actually benefit the broadcasters? Just curious ...

Yeah, they have less shows to buy and therefore don't spend so much on syndication rights.

Shows can go through their run much faster.