The main reason I keep Instagram is the same reason most people won’t quit Facebook, I have friends and family I want to stay in contact with. Somehow Instagram seems to be the less Facebooky way of doing it, or at least in my head it is.
I feel like there are many people that feel the same. That Instagram feels less like Facebook. I think the goodwill that Instagram had built up in its early days is slowly eroding and will disappear very soon.