Just because you don't need a smartphone doesn't mean you won't get one. Come contract renewal, she'll probably get an Android phone whether she wants to or not (in the U.S., it may take another contract cycle, but here in Europe, everyone is giving out entry-level Android phones from ZTE, Sony Ericsson etc as freephones)
I believe there's a relation between handset price and advanced use. People with cheapo smartphones often don't even realize that they can send emails, browse the web, and use apps with their phone. The vast majority of Nexus S and iPhone owners use at least some of the smartphone features that their device offers.
I mention this because I think GP was talking about people using smartphones, not simply owning one. I know plenty of folks who own Nokia and LG smartphones but have never downloaded an app, visited a website on their phone, or synced their phone to a computer.
My parents are still on voice-only phone plans and not even texting. The mandatory data plans for a smartphone would add $20-30 and there is definitely no interest in that.
