My DW has a Disable permit. Some days she can only walk a few feet. Other days she can walk longer. When she is OK we do NOT use the permit. Other day we do.
My Sister is in a wheelchair 100% of the time. She always uses the permit because she need to extra room to get in and out of the van.
My suggestion. Most of us need the exercise of walking in the parking lot. The permit is for people who REALLY NEED it. Because you have a permit does not "REQUIRE" you to use it.
If you use it when you do not need it, maybe God will think you want to be able to use it all the time. . . . :S