The AAAs stopped doing downloadable demos a year or two into the 360/PS3 generation because they came to the conclusion that demos convinced people to skip the game. That's why we don't often get demos.
If I remember correctly, a lot of XBLA developers were also resentful that demos were mandatory on their games because of this. And it's why MS ditched that stipulation.
If I remember correctly, a lot of XBLA developers were also resentful that demos were mandatory on their games because of this. And it's why MS ditched that stipulation.