CafePress is great for idiots like me that want a mug for myself without having to buy like 10,000...and if you want one, great. The fact is that for $15.00 for a mug, and then profit, I'ts a High Dollar investment and you are not making much if you plan to sell a lot. Lots of companies will print you mugs or whatever for WAY less, but you gotta get the inventory.
It's kind of like wanting a sweet, bottle carbed wine. You can do it, but it may not be exactly how you wanted to do it.