Devs that actually use a freemium model in this way (for games, at least) are very few and far between.
Any time I see a free game with IAP I always say to myself "ah, here's where they charge for gold/xp/coins/whatever".
Even more outrageous are the ones that provide a pay app, then transition to freemium+IAP. Nothing says "Hey, thanks for being an early adopter" better than that.
I used to hate IAP, especially after my nephew spent hundreds of real money into golds dragons or whatever.
However I changed my point of view as fremium+IAP does solve the problem of being able to try the real app.
From a developer point of view it's only one app to maintain. If further features are added, you have to pay to unlock them.
Also developing a new version of an app always been a headache for a developer : without IAP, the only way is to create a new bundle so you're back to square one when you have to maintain several versions of the same app (which Apple forbid anyways in their TOS).
On any case we never really owned any software anyway. E.g. our copy of Microsoft Office always been a licence from Microsoft allowing us to use their software.
So "App as a service" doesn't seems a bad model and in-app-purchase fit that model nicely.
Now the real problem is the security and as my iPad is used by the whole family, I deactivate the IAP on the settings and only reactivate when I need it.
If somebody want a purchase, s/he need to ask me first. It's not ideal but does one thing I love : it kills the "instant gratification" process. And that only save a lot of money to the whole family!
Any time I see a free game with IAP I always say to myself "ah, here's where they charge for gold/xp/coins/whatever".
Even more outrageous are the ones that provide a pay app, then transition to freemium+IAP. Nothing says "Hey, thanks for being an early adopter" better than that.