Naively (and correct me if I am wrong) but I think that a Pi with its 4 USB ports could handle 4 stick miners - subject to the following conditions:

Each stick would be attached to the pi by one of those USB cables that has an auxiliary power connector.
The auxiliary connectors would plug into a USB charger type device.

As an example I have a Vinsic USB power adapter that is specified as 40W and has 5 USB power outlets - so that a Pi and 4 sticks could be powered from the device.

http://www.amazon.com/Vinsic-5-Ports-Charger-Motorola-Cellphone/dp/B00L1XQBBM

I quite like this device which I have used to power a couple of PIs and charge a phone and a battery at the same time.

Whether this is sensible of course is another matter.