That was the reasoning we came up with - that if it leaked into the pool it would not be too much of a contaminant. Our pool is outside and only about a hundred feet from a lake. If the pump itself leaked it also wouldn't be too bad (it's located under the pool decking). And a petroleum product might also not be good for the liner if it came in contact with it.
The oil we are getting is the same price as EP's but at least we can get it today and not pay shipping.