Talk of expansion is most likely just another way to try exploiting current team local governments into building new stadiums. Wouldn't expansion make it harder for a team to move by eliminating a potential destination? That would take away the teams leverage. The Rays, for example, can't threaten to leave town unless there's a Portland or a Vegas or whatever that wants and can support them. That being said, expansion has recently had more failures than successes. Why expand when there isn't enough talent or fans to support them now? If expansion actually happens, sure, but talk of expansion just promotes those locations where it may happen for now. Which drives the "relocation" scam.