I have a problem with worrying whether this is 'real commerce' or whether subjectively a lot of money is being made. If someone makes money, largely it's none of my business whether this a significant amount or not.

If your concern is zoning, that's a reasonable concern if people were turning residential properties effectively in hotels. That criteria can be left to local lawmakers. However it seems in most cases people are simply using small-scale property they live in and previously would rent.