air cushioning is a feature with light stands... some have it some don't.
basically, the chambers of fill up with air when the sections are expanded and then the air leaves very slowly once you start to collapse the sections of the stand.
Why have air cushioning? If you have a heavy, expensive rig at the top of the stand, you don't want the sections to collapse jostling the bulb (with lighting) or microphones (with audio). in other words, it is assurance that your stand won't collapse too fast, even if one of the sections becomes loosened.
The only disadvantage with it is that it takes longer to break down your rig at the end of the night.