"BTW what makes you think nitrogen escapes much slower than air? Who ever told you is spouting nonsense. Air is 78% nitrogen already. This entire nitrogen in tires business is a scam for almost everybody."

The other 22% is what you're eliminating, mostly oxygen,(which does escape faster than the nitrogen) as well as water vapor, & trace gases. It's PURE nitrogen vs air, not just having some nitrogen in there. Worth doing if it's cheap & easy, but for tire dealers it's a profit tool, hence their high prices for it.