I'm living alone now, and it turns out that a cell-phone is cheaper than a land-line for the amount I use it, so financially it makes sense. I've never complained to anybody about my "minutes" unless I want to get rid of them, maybe you should be careful about who you talk to?
I agree that it's annoying when people use that excuse. It's also stressful if I'm using a phone and worrying about my own minutes. But it's so rare to use the phone during the day that I'm nowhere close to my time limit, and therefore I'm perfectly comfortable not worrying about minutes.
If I need to use the phone in a restaurant, I excuse myself and stand outside/in the lobby. In class, I never answer my phone, no matter what. I'll return the call between classes.
My phone is always on vibrate, because I hate ringing phones.
I don't mind being reachable, since there are very few people that want to reach me, and usually it's important if they do.
I think that covers your main objections. I stand by having a cellphone without a landline. Of course, it's a personal taste thing