You really have to be saavy to make it work, but for mom-and-pop retailers that has always been the case. Our local FLGS is very successful, but it is because the owner is very sharp and he lives the job. He knows MTG is bread-and-butter and he has built the business on that. He also carries way more stock on other games than he probably needs to, but when you go in it is very cool to see so many games under one roof.
He owns the building, he doesn't care that the exterior is kinda dumpy. He has maybe one full-time employee. He's there pretty much 7 days a week talking with people and making sales. He's an expert on the industry and is widely recognized as such nationally. It makes him a decent living and he genuinely loves it, but he's worked hard it for 25 years. He's also very cool about supporting things that are never going to be huge money makers for him. He hosts a monthly Bolt Action League and carries a sizeable amount of Warlord stock.