I like the idea of the service, but I am confused about the profitability here.

(I know the mining rigs are all rented now, but I am creating an example using the listed hashrate and costs.)

So if I go to http://leaserig.net/ and rent Jupiter for 24 hours, I am charged 0.0470 BTC (around $36 or so).  I get the proceeds from that 24 hours of mining.  As of this writing, the most profitable coin right now according to coinwarz.com is Franko coin, which would gain me ~$25.  Umm...profit? 

How does this make me money?  Maybe middlecoin or something gets a slightly better profit?  But 25% more?  In any case, if those calculations about turned out to show a profit for the lessee, why wouldn't the owner of the hardware use it to mine coins?

So that's what confuses me, maybe there is another way to rent these to gain a profit.  Or maybe the lessee is hoping for the value of the coin to improve and make the money later?

I fully expect that I have missed something here, please enlighten me! 

Thanks!