Other than to hide how many bots you have so people can't tell if you have more bots than users, what purpose does this serve? The list of available bots isn't top secret and users can not use the list in any malicious manner so it makes no sense to hide the list.
Seriously, this feature would make it look like you are hiding something, even if you are not. One easy and popular way to bloat your user count is to create a bunch of bots. Intelligent users know this and do /bs botlist to find out.
