The only other reasons for it that I can think of is that they're trying to artificially raise the amount of BTC they're "paying out" and/or the amount of BTC people are depositing by paying money to themselves...
or it is some sort of arrangement where the pool claims a share of the "profit" or something?
otherwise there is simply no point doing it... they're just wasting money on fees and making the unconfirmed transaction chain longer.
The last cloud mining company I knew who did something similar was hashocean.com (and we know how that ended)...
I still want to know what cloud mining company this could possibly be?