I quess it is, you just need to know where to send that MASSIVE hashpower.
Like to some new coin you expect to rise in price soon and want to get as much coins as possible before that.
That's the point of renting hashpower theese days.
Rig owners set up their rig and mine somewhere, being relatively happy about what they get. (about 0.006 BTC/MH/day at multipools for example)
Then someone come and hire their rig for 0.01. That person, if his predictions are right, could make twice+ that in a week when the coin he's using the haspower for rise in price.
If you want to hire hashing power just to mine on multipool or straight LTC, you will loose for sure.
+1
... and it has nothing to do with the end of GPU mining. These large groups of rented rigs ARE mining with GPUs.