I dont mind paying for air. I have a compressor that I COULD carry in the trunk. I choose not to. I have to pay for that consequence.
And my Kia likes to throw the TPS light on for no reason when I drive more than 100 miles on the highway. So I get to find them regularly in case I actually have to put air in. (Typically its a false alarm, and Kia wont fix because it never throws a code to prove its coming on and me snapping a pic of it isnt good enough)
Sounds like they are a bit sensitive. Have you tried Nitrogen inflation?