If an amateur can do that to your service by scraping, imagine what someone can do if they actually intend to do you harm. With cloud pricing models someone could find a little misconfiguration or oversight and put you in the hole in operating costs. Anti-abuse is a necessary design when your service is exposed to the internet.
Not saying that doesn't suck - it does, it's why many ideas don't work in practice as an online service.
Not saying that doesn't suck - it does, it's why many ideas don't work in practice as an online service.