For a guy like Johnny Archer or SVB it is likely a good investment. It gives them a free place to practice and hone their game which indirectly leads to increased revenue from tournaments, it can act to help them get cheap action/sets from the local players to help subsidize their income, it can be used for many tax write offs when associated with their professional pool career as long as they have a good accountant, and the fact that they are famous within the pool world and own it and hang out there helps market the place and get people in the door.
For normal people you lose all of those advantages.
In effect, is it worthwhile for a guy who owns a car racing team to own a mechanics shop? Probably.