It's funny, I've seen some of this same crew (some with new aliases now) do the same thing on quite a few boards, one which I was mod of and the same thing happened, though I didn't really care so I let it go.
It also happened on another board which I cared about and fought to get back.
I agree that these types of replacements should not be allowed. Anyone with half a brain can see that if they're not undisclosed IRP's, then they're a group of frontloaders who take over the board and create false interest. People see the board hit the active lists, see all the hype posts, buy in and become bagholders of worthless stock.
Granted, said suckers should not buy blindly so they are at fault too, but this kind of hype is a black eye on an otherwise great site.