Earlier quoted context omitted.
Doesn't sound like a very good alternative. You're paying 10% of the cost of the phone to protect it against (some) accidents, but in the process set it back a generation, by making it thicker and heavier. That's pretty costly as far as insurance goes.
Only if you place a high priority on thickness. I personally don't, and am actually fairly annoyed that cell phone makers don't have the option to e.g. double the thickness of their phones in exchange for a 2-3x increase in battery life.
Most people do. This is why smartphones have been getting thinner with each iteration.