Sorry to hear your locals are going slow...
Same thing's happening down here in South Florida, because there's a few problems with the newer venue due to football season (it's a sports bar) starting. New promoter's done great with upgrading the tables and balls, but noone's been able to step up to the plate to keep promoting the weeklies on an individual basis. Also keeps the group more social, of course, despite the typical diversity of backgrounds, families, work situations you find among foosers.
If noone among you maintains contact with personal texts, emails, and phone calls weekly to the regulars, (not the crappy broadcast form texts or form emails), your local will naturally drift away every so often. I hope someone or even better, several people, decide to keep that personal touch with your regulars happening. And even more importantly, any new foosers that are prospective regulars. New venues always start off nice and fresh, but as people get out of touch, they find other things and other places to do, without being regularly reminded.
I hope you guys get back into a really good season.