And your evidence is ... ? It seems to me there are more than enough cheap and crappy Android handsets out there to serve the feature-phone market too.
Depends where you live. In Ireland, for instance, if you walk into a shop wanting a prepaid phone, you're pretty much getting an Android, with most telecoms. Three, for instance (generally the cheapest major telco), currently lists precisely one non-Android phone in its under-100 euro category, and it's not a feature phone, it's a Symbian smartphone. The rest of its cheap phones are Android, mostly 2.3 and 4.0/4.1.
You could buy a feature phone separately and bring it to the telecom, of course, but normal consumers don't do that.
Three, and every other telco, has a vested interest in getting you to buy something that they can sell you data for [1]. Argos will sell you an unlocked Samsung phone for 19 euro, Nokia for 25.
[1] of course, Three doesn't let you use that data because their network is a joke, but that's another story from the annals of "Ireland may be wealthy, but our infrastructure sucks so hard CERN has a contender for accidentally opening black holes in atmosphere"
