Our local Costco uses nitrogen in all new tires. The reason is the moisture content. The moisture in the tires expands and contracts at a higher rate than dry air(atomospheric or from a bottle). If your compressor could remove all of the moisture, you'd get the same effect. The higher the moisture content, the more the tire pressure varies with temp. It is not snake oil but a good way to help maintain constant pressure with changes in temperature.
Dan

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2012 E350 Bluetech