B&W isn't in any real danger, IMHO. I expect to lose access to Kodak and/or Fuji films within 5 years because their production facilities are too large in comparison to current demand, but Ilford and a couple of EU producers will keep going as they're profitable at their current volumes. If/when Kodak goes, I expect Ilford to thrive. I'll be real sad about the loss of TMY2 and Portra, but I'll get over it and shoot Delta instead.
In the last thirty days? I, uh, just bought 100 rolls of Fuji B&W off Tri in another thread. But normally I only buy once or twice a year, about 50-100 rolls at a time. I realise I'm not the median user, but there are plenty like me.
I never buy from a local shop (Australia), because it costs 3x as much as buying from the USA and paying shipping. I don't expect my local shop to survive on film nor to keep carrying it, but I'll be sad if they stop stocking chemistry, and I do support them with regular purchases of the 5L Ilford concentrates.