I just paid $60 (no commitment/contract) for a Lumia 640 (it was a gophone, which works fine on my regular AT&T plan). It's a reasonably fast, decently built phone, and I must say the Windows phone UI is starting to grow on me (and I HATE windows 8/10 on the desktop).
Besides voice calls, I use a smartphone mostly for texting, email, web browsing, maps, music, and the occasional (netflix) streaming video.
A $60 phone can now handle all of these things easily, so I would be stupid to spend more (vanity? status symbol?). If I drop it onto the sidewalk and it shatters, I'll merely sigh, mumble something obscene, and go buy another one. My reaction to dropping a $600 phone would be a bit more... extreme (mostly because I can't afford to replace a $600 phone on the spot).