DDOS server when not making direct purchase. If there is a financial incentive the process is automated to generate maximum value for the scalper. In our modern age scalpers are not going to be waiting.

Biggest impediment would be changes to purchase process. Run one live user through and repeat for how many bots you want to buy more.

Agreed with your comment on random being better. I just found a scalper sitting at a PC for 20 minutes waiting to buy pretty funny.