You just have an 'oudated' setup. 110, 119, and 61.5 was a typical setup in some areas long time ago. Over the years, Dish has moved channels around to different satellites (and added new satellites too). If you can get the 129 sat from where you are, you can move the 61.5 dish and aim at 129 to give you all the channels that 99.9% of people care about. You can always call Dish and tell them what channels you want and they can tell you what setup you need and/or come out and upgrade.
There is channel overlap on some satellites because people have different dish setups depending on where channels were located (on which sats) when you setup service. Currently, just about everybody either gets an EA setup (if you live in eastern half of USA) or WA setup (if you live in western half)... But they have to keep some eastern arc channels on the western arc still because say, folks like me, live on the east coast but still have satellite dish pointed at 110, 119, 129 (which is the western arc).