I've read this entire thread...some interesting perspectives and ideas for sure. Some are insightful, and obviously come from some real life experiences.
The conundrum, I don't think is pool being in bars. I think the real conundrum is that pool ONLY exists in pool rooms and bars today. That wasn't always the case. Pool use to be found everywhere. Schools, social clubs (both adult and kids) and many places in between. Businesses that otherwise had nothing to do with pool or bars, etc. Pool was not always so isolated as it is now.
That being said, as someone who sometimes dreams of owning and/or operating a pool room, one idea I would investigate would be hotels. Hotels exist pretty much everywhere and are in the business of leasing affordable space. They have local and out of town clientele, and many also already have restaurants and bars onsite. Hotels attract business by what's available in the area, and some areas don't have much to offer. This is not something I've looked into heavily, but there seems to be synergies and opportunities for the right plan. Obviously, not all hotels or locations would be viable candidates. Like every business, you have to know your market and customer base extremely well.