It seems to happen in the ETH threads in Altcoin Discussion/Speculation a lot.

They just seem to use text spinners and copy & paste (or use bots to write) the same replies over and over just exchanging certain words with other words with the same meaning. Some spinners can even change sentences around and all that.

It would be nice to have some board where signatures and avatars are not shown at all (and not counted for Sig campaigns).