>I think a CAPTCHA in the ordering process would make more sense.

There was another thread here a while back where someone shared their experience writing sneaker scalping bots. Apparently, CAPTCHA tokens are valid for a minute or so, so this guy would solve heaps of them just before the form went live and cache the validation tokens.

Then, when the form went live, the real humans who didn't have cached CAPTCHA tokens would be slowed down even more.

Net result is that the botters ended up getting an even greater share of the supply than without CAPTCHAs.