Absolutely, like I mentioned, there was one 9* team at first with others all 7*. And a team we were devising a strategy against for one of our association members had all 7* players. Their 9* leader was loaning all his team when we first looked.
Pass one hour and we were back to devising strategies, suddenly now there were two teams with 9*, clearly, that team suddenly transformed. And support confirmed it, THAT team cheated.
I guess their team leader with 9* thought "oh man, we can't compete with 7* teams with only 7* and a few 9*, hey mate #2 here's how to do it....we need more of those excellent 9 starsies. " :P