I don't think I've ever used a air pump at a gas station so providing free air pumps won't get my business. One thing I've noticed is that more and more stations aren't providing a squeegee and water to clean my windows. Either the bucket is empty or increasingly it isn't even there.
One reason station owners don't provide free air is the cost of a compressor if someone damages the hose, etc. Several thousand dollars shot as the compressor flogs itself into oblivion. Hoses have even been cut intentionally. The no water or towels to clean my windows is not good. I quit those stations that repeatedly fail to provide them.
I still instinctively go to the stations which provide free-air access, though I rarely use their 'free' pumps too. But whenever someone asked me about where the gas station(s) are, these are the one which pop first in my mind. Also I didn't find these free-air stations charge more on their gas, compare to the other stations next to it. But pricing is mainly location dependent....
What I've found is that all gas stations will accept coins, and that all the gas stations that I have been to will also provide air for free; the best way to find this information out without seeming stingy is to go to the clerk with some singles in your hand and say "Can I get some quarters for the air machine?". If its free, they will tell you; if its not, but they don't have quarters, they will just turn it on for you; at worst, they will give you quarters and you can go put them in the machine.
OMG! They charge for air? In SA we can have all the air we want at the gas station. I prefer to use my own compressor (with moisture trap) and digital pressure gauge.
You can just pull into the shop where I work and sombody will check your tires and adjust pressure. Free
We mostly go to 76 stations if we're not getting gas at Costco; air costs 50 cents unless you're a paying customer. I was at the state emissions testing station on Saturday (for my Saturn, not my Prius!) and noted they have free air. We have a 12v compressor in the emergency kit in the Prius, but its guage is pretty inaccurate.
