you not aware how massive the gaming community has become on android devices? it's just even over-taken apple in terms of phone OS's.
i think (and hope, as i'm developing for ouya/android), that people will snap up the opportunity to play these games on their tv, especially for £50-£100 for the machine to do it (as opposed to £400 for a phone that does it, or as well as).
I think your logic is flawed. The phones are the reason for the high uptake of Android game players, not the software itself.
People get the phone they like then they play the games because its there for them, not the other way round. This means that most Android players couldn't give tWo s**ts about a dedicated gaming device to plug into their TV.
EDIT: Also, you mention cost of phones but I cant remember ever having to pay up front for a mobile phone!