Well I'm no programmer but I'd think it safe to say they don't have to set a bot to spam a bunch of reports back to back, they could set up intervals and with the complexity of programs today I'm sure they could make the times they report to appear to be random. Now you have 100 RMT character-bots doing this and you run into the same "appearance" as a bunch of legit players making reports. I don't think it would be hard for RMT who have proven to be quite resilient to find a work around and 'cloak' themselves amongst the players.

At least by forcing players to have to write a report it weeds out potential bots (because human writing is different that generic bot writing)