So I've heard that hitting your unwanted neighbors well make them stay not move! So what if you did this to your wanted villagers? Would they stay in your town forever?
Hitting unwanted villagers puts them into the "befriending" status, where they are supposed to be less likely to move, as opposed to fully ignoring them. Your favourite villagers will have the "best friend" status with you anyway (at some point) and in that status they are more likely to move. I don't think that teasing them lowers your friendship and puts them into befriending, and would you really want to lower your friendship with your favs anyway?
Once you have your dream town, someone will want to move anyway, so at that point friendship doesn't even matter.