Too f*cking many. I picked up a part time gig at the local running store about a year ago, so it gave me access to lots of perks and discounts. I went a bit crazy trying new things because it was easy to just pick up a new pair for like $40 every now and then, but I was only locked into certain brands(Asics, Brooks, Mizuno, Sauconcy, Salomon). Turns out I hate most of those brands after trying their shoes and now have a bunch of shoes I don't want to wear. It was pretty bad when I've got brand new pairs of shoes from those brands, and I would choose to run in my year old pair of Beacons I already had, with like 500+ miles on them instead.
I actually just started cleaning and donating the shoes I don't wear. I shelled out for some new Beacons, no special rate, just regular sale that anyone else would have access to, because I know those shoes work for me and that's gonna be my go-to pair. Decided to just cut the BS, and just be done with it. I had my little adventure and learned my lesson.
Moral of the story, run in what's comfy for you. Don't follow hype or sales.