PI used a generic code for UR production and placement and seems to have placed no limit on the number of times or amount of spawns a conquered nation can support. Hopefully they will take a look at this and make some corrections in a future patch.
In principle, I agree that since URs don't consume manpower, it's silly that the French people can rise up in revolt twice a year without any further consequences (where are they getting the warm bodies, anyway?). I also agree that it is too easy to supply an insurgency. Even with no naval bases in range, the US can spam URs in Europe. How are they getting the supplies there?
That being said, if I thought that uprisings were a bigger threat, then I'd be more worried about them. In practice, they are just a cheap way to gain a tiny bit of experience for the troops left behind in occupied territories. Uprisings hurt the AI more than humans because of how theater AI overreacts (Theater AI basically says, "ZOMG! Send ALL the Panzers!").
To put it in perspective, I might get 6 or more uprisings in Poland per game, but none of them achieve the longevity of even the defeated Warsaw Ghetto uprising. It's quantity over quality in 99% of cases. Human players are wise enough to hold back a mass uprising until they can coordinate with something (like Overlord) to make the uprisings worthwhile, but the AI just kind of spams them just enough to force you to garrison the rear a little better.
That being said, if I could change anything, I'd make it more expensive to set up URs in far away countries. If you don't have a naval base in range, you pay double or triple the cost. This might tone down US support for insurgencies in Axis countries while not making it impossible (it might also encourage the US to invest in URs in China instead of Europe).