What would it take for MLS to buy out/merge with the A-League?

After reading about the Toronto rift and realizing some of the best soccer cities/markets for possible MLS expansion already have existing A-League teams, why not merge the two leagues or buy them out. I think of the AFL merging with the NFL as an example. Also the NBA in talks of buying out the CBA before they decided to start their own developmental league. Most A-League teams have their own stadiums/venues, already marketed and have a loyal fan base, and are active intheir communities. Those are several of the prerequisites MLS is looking for when considering expansion teams. Yes the talent pool will drop off for a year or two. But our MLS teams cannot keep on getting younger and younger as new and more skilled talent continues to develop, pushing away talent in their mid- to late- twenties. I think in the long run it will be good. There will be more owners, more teams for player development, a larger pool of players for the US National teams, it will grow the WUSA expansion for their league, more sponsors, more attractive to the TV dollars, more opportunities for coaching evelopment, more international visibility and attraction, and the list of pros goes on and on and on....Your thoughts?