just throwing something into the ring here.
But it isnt cheating. They arent using external program, probably spawning bots then retrying then killing them. Not cheating now is it? Dishonesty yes but not cheating in the same way aimbots are.
Perhaps if valve fixed their own issues such as not letting bots add to stats then this would solve a whole host of issues. Personally I am against stat padding and idling etc etc but I would rather valve fix other bugs in TF2 than worry about stat padders.
Its not the cough that carries you off but the coffin they carry you off in.