This doesn’t have much to do with rents gone awry in Manhattan, but:
Musical instrument shops where you can actually walk in, have a chat to someone about the pros and cons of a particular item with someone likely to be an enthusiast as well as an employee or owner and walk out again with whatever it is you have decided to take the plunge on are another good example of the kind of business I dont want to see go away.
The only way I know how to follow through on that is to actually go into my favorite store and actually buy something every now and again, even if could get it a tad cheaper online, instead of just taking the “free” advice and then running off to actually buy on the net…