There's no cheating.
first of all, you can't have more than 15% extra bonus furing matches.
Second, to receive all 4 different boosters, you better send 4 different bossters also to different friends. Better chance to receive the send ones yourself.

But there isn't any rule who said that having more than 1 account are suffering any penalty at all.....
\Having multi-accounts, he has is very very lucky to play with all teams on the same server!