I think directly monetizing the use of the tables is only going to put people off, and have the net effect of discouraging people to buy and play at the local store.
I agree I' don't know what the long term answer is
You say that as if gaming stores are a dying breed. Are they?
I think that people' gaming community spirit, and the norm of encouraging people to buy where they play tends to work.
It doesn't capture everybody, but it seems to capture enough people. I also know people who play, but buy online, but still contribute by buying drinks and snacks at the store where they play. Myself, I buy product from the outlier store that's closest to me, and who has the loyalty program. I play there, but I also play at another place that sells drinks and snacks. I buy mostly the former. Also, because they do card sales only, and no card sales at <$5, so that means that I pick up card sleeves, or paintbrushes there as well.
I think that the success of your gaming stores will depend on your local culture. I realize that I live in a Mecca for gaming. We just had another store open a month or two ago, and they're going gangbusters. (Lyraeus and I were even there tonight.) They're also one of our five stores running a Sullust tournament. Not much before then, there was a different gaming den (most revenue comes from food and drink, and a smaller selection of games sold) that opened up, and their event organizer was pimping his place pretty hard in the community. Now they have a light rail line that will make it easier for the carless to get down there.
The point being is that my community's culture has norms that help gaming stores survive. A community spirit helps that work. But if your broader community has social norms of buy-it-cheap or don't-play-with-people-you-don't-know, then FLGSs are just not going to thrive in your environs.
I also run the Armada league that is being set up there and we have a growing community (i may have bought a core set, gsd, imp squad pack and dice for the guy. . .but hey he now loves it!)
Portland is spoiled for choice. . . the FLGS that Mikael and I went to last night is fast becoming my favorite. Simply because they are friendly and interactive which to me, is VERY important.