This effect is a real problem, but I think it's a mistake to blame the trappings for it, as you rather reliably and prominently do when the topic of cameraphones comes up.
Personally, I clearly gain leisure and peace of mind from having a phone---whether the "smart" aspects are a win over just voice and SMS, I'm not completely sure yet, but SMS works drastically better with a smartphone than it ever did with the old feature phones. Just the time saved in extra trips to the grocery store, because I get the message that says "We need garlic!" while I'm there rather than having to go back for it afterwards, is probably enough to make the device a net win.
I don't find it to be a compulsive source of distraction. Maybe I'm just lucky, or maybe I got that stuff out of my system when I was a lot younger and computer networks were a novelty. I think you have it backwards, though; humans *find* distractions, and if you take one thing away we'll find them in something else. Hence the perennial series of moral panics over new distractions, going back to at least classical Greece and all sounding much the same in spirit. Our cave-dwelling ancestors no doubt flipped their hirsute lids over how much of a time-wasting distraction this "language" crap was.
-NT