Cell's potential may be wasted, but when their primary strength is in scientific computation (very large number of floating point operations on very small set of data) which games have very limited applications for (physics, signal processing, and...?) it's kind of difficult to ask developers to change their games.
It's like, if you take your vegan friend to a Chinese buffet - sure there's lots of food, but your friend can't eat most of them. Asking for a paradigm shift at this point is like asking your friend to stop being vegan.