Even in those situations, I can't see why I'd want to go with BatchPCB.
Seeedstudio's "Domino" service is equivalent to BatchPCB except you pay $49 shipping and $0.75/sq inch. This becomes cheaper in total than BatchPCB at about 40 square inches (around 5-6 Arduino-sized boards). And once you buy in to the $49 fee you can comfortably buy as many different boards or copies of boards as you want, even throw in a couple of ladyada protoboards for about $3 each, or other open source projects you want to try. With Bathc PCB, this is simply not an option because their per sq. in. price is so high.
My personal preference is Seedstudio's "Trinity" service though. $90 for 80 square inches of up to 3 designs. At BatchPCB, $90 gets you 32 square inches.
And their propaganda service gets you 5 boards for $30, up to 4x4 inches. With the catch being that you have to open source your design. They're basically subsidizing open source hardware in that context. They're bribing developers to share their designs. How can you not love the company?