I can't see a possible need. Little plastic card in my wallet brings all the help I could need. That's why I pay not just for AAA, but their top service. I honestly can't remember ever needing a jump while on the road anyway. I've used them in a boat (totally different animal), I've used a plug in jump starter at home in below zero weather on a battery I already knew was dying, but...well, I don't run my freakin' batteries dead! Even if you get a jump you still just about ruined your battery if you run it down.
I would never take a jump from a stranger, people are homicidally crazy these days. I would never give a jump to a stranger for the same reason, and also the added liability...what happens if something else in their car breaks, even unrelated, or somebody gets hurt and they try to sue you? It's not uncommon for batteries to blow up during a jump, especially if somebody screws up and clamps the negative to the battery terminal and makes sparks. If it doesn't seriously hurt somebody, it will ruin a paint job. I've seen it happen.
Sure...it might take AAA an hour longer on occasion...given the extreme rare need, (never, that I can remember) I can wait.