That is true, but think of all of those satellite receivers out there on the market. I bet there are way more Dish/Directv receivers out there than FTA receivers (in the U.S.). The thing is most are probably leased though. If people bought their own Dish/Directv equipment then it would save the satellite providers from having to come up with the money themselves. Later on this could lead to subscriptions for the providers. They could require MPEG-4 equipment in order to get those FTA stations. It would be VERY VERY easy for them to start doing this. They got oodles of space and it wouldnt' take much.
That would be entirely against their business model, at least their current one, which is make the up-front costs as low as possible for the customer, in exchange for long term monetary commitments. A good deal of their growth has been becuase of that model. If they began selling recevers at their normal price, the takeup would drop.
However, they could offer both options though.