I've really found that the "anti cell phone" thing is largely a generational thing. (cue someone pointing out someone they know who's younger and doesn't like them either, but I think it's true overall.)
When older people grew up, there was no caller id, and the only chance of someone getting ahold of you was when they called you at home. When the phone rang - you answered it. It was like a Pavlovian response - ring == answer. Even with answering machines, if you didn't answer it and someone didn't leave a message, there was no way to know who called. Not answering your phone was sometimes like not answering your front door - people just didn't do it, it was considered very rude.
In the generation that grew up with cell phones, the "you constantly have the phone one you" has led to different etiquette. When you simply cannot answer your phone the instant it rings, it's led to a whole different thing. Super needy girlfriends and overactive parents aside, for the most part the younger generation is used to getting a phone call and not answering it. I'm right in the middle in age myself, but especially my friends younger than me have a tendency towards the opposite problem then always answering the phone...they have no problem not answering it. Like, ever.
I'll take a second to point out that I'm talking in generalities here, and certain there are many, many exceptions. But I think the hostility towards cell phones that you see more of in the older generation is that they think of a cell phone as "a way for people to call me that always has to be answered". To them (and not all of them, but a certain segment), it's a leash that keeps them from relaxing. And it's not just that one person's fault either - once other people with a similar attitude find out they have a cell phone, those people start expecting that person to be constantly available. And get upset when they don't answer their phone - their wife gets angry she couldn't reach her husband at the supermarket, she gets upset he didn't answer his phone while biking, etc.
I have the darnest time getting my dad to use his cell phone in...well, what I would consider an "appropriate" manner when we're on vacation. To me, it's a "mobile communications device" that can act as a whatever category I choose for it without any guilt about it whatsoever. To him, it's always a phone that's supposed to be answered when it's on. It's like, we go on vacation, and I'm like "great, we have cell phones, I can relax and not worry about getting separated, or I can go and do my own thing without worrying about meeting up later to much". For him, it's like "time to turn the phone off". I always give him crap like "wouldn't it be great if, like, someone invented a device that allowed us to, like, "call" each other, or something, if we got separated?"
And I can see why he wants to turn it off. When a friend of his calls him in the middle of the hike he takes the call - something I would *never* do. Ok, ok, if my caller id said "Scarlett Johansson" I'd probably take it, but *otherwise* I'd *never* take it.

It just doesn't make sense to me to answer my phone in the middle of a hike. I mean it's a cell phone - that's why it has caller id, voicemail, and text messaging. It's so I can *choose* whether it's important to answer the phone right now.
To the older generation (or perhaps someone in a very needy relationship), the cell phone is a phone that has to be answered if at all possible when it rings, like the phone in their parents house did, so it feels like a leash. To most of the people who grew up with cell phones, it's a mobile communications device that may or may not be answered depending on the situation, which lets you have a far greater deal of freedom when you have it on you as it lets you have the choice of calling people, having it in an emergency, etc but you don't have to. It's really freeing - if I get lost and separated on a group ride I can use the gps to tell me which general direction my car is in. If I want to see if someone wants to have supper at the end of the ride I can give them a call at the end of the ride - and I don't have to rush through the ride because I made plans with them at a certain time. And obviously if I have a serious mechanical breakdown (my bike frame broke once), it's available if I want to call for help. I find it very freeing.