The color buttons work just fine on 20.x and 21.x remotes. The 722/622 just doesn't do anything with them.I wonder if Dish doesnt activate the color buttons on the 20.x and 21.x remotes, because you can(and they do send out still) the 5.x and 6.x series remotes for 622 family receivers. It would require completely different sets of software for each remote, compared to each remote acting the same currently, depending if it is IR or UHF.
On a Hopper or 922 you can use the 20.x and 21.x remotes and have full functionality including color buttons.
They could enable green button cc functionality on the 211/222/622/722 receivers, but I doubt they will. They'll just consider it a Hopper feature and another reason to upgrade.