50% of the natives who belong to these reservations already live off reserve, there is no reason that the other 50% can't as well. Instead of spending money to keep them on the reserve we would all be better off to spend money on getting them off the reserve.
I understand your thought process that maybe "buying them out" and providing funding to resettle in "civilized" areas might seem to be a solution, on the surface. But that's just a modern-day version of genocide, without the massacres.
Imagine if a small "white" town in New Brunswick, or any other province, was in a situation where their provincial government found it inconvenient to plow the roads and assist with other services. And imagine that the provincial government said, "Sorry, we're going to force you from your homes and make you move into the city. It's inconvenient for us that you want to live there." Imagine the furor.
Some of those who continue to live in the FN communities today would no doubt love the opportunity to go to the cities. But for some of them, it is their home.