But how much market share do they have among people likely to buy expensive digital photography equipment?
Lots, because it is cheaper than buying an iPhone off contract or even taking into consideration the monthly contract rates, in countries where most folks get to see 1000€ or less monthly.
Folks that get to see "1000€ or less monthly" don't care about a novelty camera-first phone. They can get a good phone AND a better than the Ektra compact for way less.
Which is my exactly point regarding the iPhone use as camera.
Given that outside US and a few other countries they have a market share around 20%, and most of those countries use pre-paid mobile phones, I think there are plenty of opportunities there.