I'm curious, what's the market for that? If we had more than 100 full cockpit A-10 simulators in the nation built to the fidelty that warrants a $15,000 stick, I would be truly surprised!
Supply vs demand. I'm sure they'd build fewer units, but for a higher cost (arbitrary example: $45k a unit instead of $15k). From what I understand, they deal primarily with military and .gov sales. Again, from what I know, they build this stuff on-demand, so it's not like they have a huge stock of it. Everything is milled from the same (or equivalent) materials as specified in the TDP for each aircraft, so it's expensive and time-intensive to produce.
Remember that while the upfront may even be higher than the real aircraft (as is the case with many FTD's), the lifetime cost is usually much lower and the lifetime of the product itself may actually be longer than the real thing.