I think the problem is that DYIers vary by skill and knowledge, and the problem WAS that too many DYIers really didn't understand completely what they were doing which led to poor experiences with the Dish product which leads to people bad-mouthing Dish and thinking the service is lousey when, in fact, that particular DYIer installed a MESS and couldn't peak a reflector properly if his life depended upon it and lose signal periodically and then he has incompatable or the wrong equipment for what they need. Dish want to install to ensure that it is the best possible, and they will stand behind that install.
It really is far more complicated tody to KNOW how to DIY a DBS sat install. Yes, back in the 1990's I would say just about anybody who could hammer a nail could install a DBS system, but not today. It takes a lot of research to understand what is compatable and necessary for your particular install to be done well and to be reliable and certain it will work with your particualr STB's like ViP's and Hoppers. Both Dish and DirecTV have a lot of generations of equipment that are compatable, but are NOT compatable and then look at the wrong sats. This is not a criticism of you, but does apply to most of the DYIers who think it requires little knowledge. So, to prevent such negative experiences, Dish will often require that one of their techs install because MOST people will mess it up.
As others have stated, but I'll say it, as well: there is no money savings nor advantage buying all your own equipment as opposed to having Dish provide it. You still get charged the same amount of money per month for any active boxes, owned or "leased." The fee is just given a different name. Also, if you own the box, you can get it RMA'd and it will still be owned. That has been my experience over many years with different boxes. Getting your own equipment could even cost you more EVEN IF you cancel Dish service before the 2 years. Someone on here did the math, and I think after 2 or so months, your Early Termination Fee is LESS than if you had purchased the equipment at retail.
Back some years ago, buying boxes was necssary when Dish only subsidized TWO boxes. Later, Dish began subsidizing FOUR boxes, but if you needed the last 2 boxes for a total of 6, then you had to buy and own the remaining 2. Today, with a Hopper system, I think it is a maximum of FOUR Joeys to a Hopper that Dish subsidizes. I think you can add more Joeys for other rooms (you still have the same limit of number of streams due to the technology), but you pay for that and will own.
No point in owning any Dish equipment. It has been many years since it made some sense to own Dish equipment. Yes, as a 721 user, I had not choice but to buy, but that was a LONG, LONG, time ago.