As someone who buys a lot of apps this is very disappointing. Things that would make me buy MORE apps (demos, upgrade pricing, better support) are still not in the app store, meanwhile the one pricing model I detest (subscriptions) is being added. I suspect I'll be buying far fewer apps if there's a mass movement from a purchase model to a subscription model among app developers. I'm perfectly happy to pay $20-30 for…
What about $0.99/mo, or even $0.49/mo? My initial reaction is the same as yours, but I could see myself agreeing to $0.99/mo for some of the apps I paid $2 or $3 for. Still relatively cheap for me but would dramatically increase income for the developer.
If you're talking about an app that's a major part of your workflow for something, maybe this makes sense. But most of the apps that I've paid $2-$5 on are things that I'm only likely to fire up occasionally when I need them. Monthly fee to mark up photos or scan papers with the camera? I'll pass.