To be fair, I don't think it's been heavily advertised or constantly mentioned in the news.
So a lot of casual consumers likely don't even know about it.
I only found out about it less than a week before release when I got an email newsletter from a case company saying announcing new cases for it. "iPhone what?" I had to Google it!
And I'm fairly certain I'm their target market. Was using a 16GB (it was free...) 5s that has been full most of the last 2 years I've had it, so much so that I was still running iOS 7.1. After seeing how much the 6 still sold for after the 6s release, I was planning to just give up and buy a larger capacity 5s on eBay.
If the sizes had been 32/128 at the same prices, I'd have thought Apple was playing an early April Fool's joke, they read mind so well! (16GB should just be sold for business, not consumer use, Apple will make up for the few people that would've bought the 64 if there wasn't a 32 in *App Store* sales for *all* increased capacities. Most people buying lowest capacity devices for personal use are buying "cheapest", not because they actually know how much storage they'll need)
6s specs (don't care about 3D touch or a barometer much, and I don't take selfies), better camera with live photos (wizard photos!), more space, comes in rose gold, fits my existing cases, still fits in pockets of women's pants! I like the 5s design better than the 6 (camera bump WTF?), what's wrong with taking a still gorgeous, functional design and making it better inside? It's not ready to be retired yet.
Perhaps unsurprisingly, I'm using it right now to type this. My carrier (Koodo - Canada) had them in stock on the weekend, someone else was buying a space grey one at the same time I was, and not everywhere had gotten them in yet - they were the first to update their website with them, too.
So I'd have to say yeah, a lot of the atypical-for-iphone sales are due to people just not knowing about them, and lower stock levels, which I can't help but think, due to not everywhere having them in store for release, Apple anticipated.
Why would you heavily advertise it anyways, when it might cut into your iPhone 6s and people-waiting-for-7 sales if you didn't? A slow and steady predicted sales rate requires less phones at launch and may be easier for shipping and production, also? Your target market is not early adopters anyways (though it does seem to be catching what I consider a slightly unexpected part of that market, those with small hands), but people who just look for a new phone when they need one, and will so find it when they look, in the spot the 5s used to be sold.
That *anybody* went from a 6s to this and are very happy with it has sales of the SE exceeding my expectations, anyhow.
