I kind of doubt that users of low-end phones know what Android is or know what they're missing. It's not like they're downgrading from an iPhone, they're probably upgrading from a feature phone. And even the worst Android phone is much nicer than that.

Eventually they will upgrade to a nice Android phone, and will enjoy the enhanced user experience. But cost does matter to some people, and although browsing at 320x240 is hardly ideal, it's probably better than not being able to buy food for a week.

(I personally use very few apps aside from the default Google apps. I mostly want to receive text messages, make phone calls, and browse the web. Apps, to me, don't add much value when the app-maker already has a perfectly fine website.)