Seven years on ...
Why Wanderer is obsessed about "winning" after seven years, in spite of many offering similar sound refutations of his argument, is beyond me. He could have obtained a PhD in Chemistry or Physics by now, and clarified for himself why there is a difference between rigid, closed containers (where inside and outside pressure differences are managed by structural strength) and flexible walled containers, like tires, balloons, hot air bags (!?) etc. where the inner and outer pressures are always in balance, by virtue of the soft chamber expanding or contracting until, like magic, the pressure per square inch of the stretching surface matches the psi of the outer realm. Relative pressure, as measured by gauges, is valid because it reveals how much the tire can safely bear under a load. Variations of small amounts exist, but may not matter greatly, depending on the tires, loads, etc.
Because the atmosphere is very thin and light - that 14psi at sea level = the total weight of the 20 miles of air above - changes are relatively less consequential than say going hundreds of feet under water, where every 32 feet = 1 atmosphere of increased pressure. Filling a tire, or your lungs, 160 feet down, then surfacing without letting air out will expand fivefold, in order to maintain the now much lower surface pressure. Trying to contain the air works in rigid walled cylinders, but will mean the cylinder is now a pressurized canister; trying to contain that air in lungs will likely damage or kill you, because they will expand beyond tissue limits and explode like rubber tires that stretch beyond their limits. But I'm sure Wanderer is just going to keep on winning.