There are some very qualified people who simply cannot use the Gen 3/4 grip frame because the finger grooves are in the "wrong" place for them. They do not buy into the idea of grinding their frames. These guys covet Gen 2 glocks and have paid close to that (or as much) for theirs. I personally know 2 such people; they definitely don't smoke peyote, and can out-shoot both of us...
.
My reference was for people who think gen2's are unavailable and would pay $575 for one