Some people are willing to make that sacrifice because their limited feature set doesn't impede on their day-to-day use. I know quite a few people who use their phone for nothing but texting, a camera, and two factor auth.

Hell, I, who would be considered a power user, spend 99% of the time on my phone browsing the web, Reddit, some Facebook, using a calculator, or taking photos. Most of my computing is done on an actual computer because the form factor of a phone just doesn't satisfy my needs.