Earlier quoted context omitted.
Sure, it's cost prohibitive now. But what about in five years? Or probably even less.
Then you have a new type of captcha. That has always been a cat and mouse type of dynamics, captchas have been evolving, techniques to break them too.
You're in a desert, walking along when you look down and see a tortoise. It's crawling toward you. You reach down and flip it over on its back, its belly baking in the hot sun, beating its legs trying to turn itself over. But it can't. Not with out your help. But you're not helping. Why is that?