I would think they're going to HAVE to limit the presale. As you say, if some whale comes in and buys up 1 Million packs or some ridiculous number, they could basically make millions of dollars reselling them later and deal a pretty significant blow to the game and user experience in general.

In my mind, they almost have to limit the packs per day/week per account. Yes, people can scam the system and open up multiple accounts, but at least it will slow the process and allow most users a chance to participate.