That is not common.
There was an issue several years ago, with the squared-off front storage compartment doors, that would crack like you're describing. The rounded doors generally don't do that, unless something else happened. The "something else" could be simply a too-heavy-duty tow vehicle, or too stiff WD bars, or even towing for extended periods on really, really rough roads.
The cracks are stress cracks caused by flexing around the door.
Photos would help a lot.