Earlier quoted context omitted.
One potential problem with that is that Amazon can retaliate by closing the users's account if they didn't agree with the charge-back even if they're unsuccessful at fighting it. That can be really difficult to deal with if you're also using AWS for hosting or other things.
Whenever I see comments about how "Company XYZ deleted my account after I issued a charge-back!" I ask: Why would one want to continue doing business with a company that made you issue a charge-back? Charge-back is pretty much the nuclear option of last resort when you have exhausted all avenues of redress. You're basically doing it to get your money back and "salt the earth" as you leave. I've done a few charge-back…
I have no idea about the frequency, but I have reason to suspect some are quite frivolous.
Like you, I believe it should be the last option. I'm just not sure that we are the majority.