1) They say that earnings will come out at a certain time, so they better be out at that time or else the SEC comes after them. If they just posted earnings as coming out at say 12:00:30 instead of 12:00:00, that just shifts the problem 30 seconds later.

2) The bots will just run for an extra 30 seconds, and will still have the advantage over ordinary people.

(Something I'm not clear on: regular Google - and Hacker News, for that matter - will sometimes just make a user's connection slower if they repeatedly hit it with traffic. Why not use that on bots that hammer the investor relations site? It completely disincentivizes these bots if the 100 requests you made at 11:58:30 mean that you get stuck with a 5 minute delay and don't get the information until 12:03:30. Or maybe they do use this approach and the SRE in question just didn't bother to tell me.)