Coffee logs

We throw out a lot of used coffee grounds at work. I'd not-very-seriously considered taking in a waterproof container sometimes and adding to them my compost heap (apparently slugs are very sensitive to caffeine). But having seen http://www.java-log.com, I'm even-less-seriously wondering where comparable quantities of wax might be being thrown out.
(Via Grist. A linked article says another company has something similar "made from used church candles (30 percent Lutheran, 30 percent Catholic and 40 percent all others)", so I supose churches would be the place to start looking for wax.)