ummm yea, you'd still be watching their programs & commercials (unless you DVR), that's really sticking it to them!
In fact, if you think about it... you're still paying Dish for that programming. Dish still has to give the money to the affiliate. So they're not out anything. If you are actually in a dispute (channel blacked out), unless you've called to complain and gotten a discount, you're STILL paying for the programming, it's just Dish keep all the money. If you've called to get a discount, NOW Dish is out some money (because any discount is going to be more than what the station is charging Dish).
Last but not least, many people won't even consider OTA or won't put in the time, money, or effort to get it (which doesn't make sense to me),