I sell a lot of taps, but it comes and goes like most items. Regular taps usually go for a buck or two; small ones 0.50. I can usually get 3 to 5 for pipe taps, unless they are big (inch and up), then I can get about 10.
I will caveat the above by saying that I sell most of my taps at tractor shows and car shows, where people who really need and use taps buy.