It wouldn't work, you couldn't carry what's needed on the back of a quad, yes you could carry a compressor that's big enough but the time it would take a fill a bottle directly would be impractical and dangerous. When filling paintball bottles fast fills are to be avoided, a fast fill generates too much heat which is not good. Normally a compressor is used to fill an air bank which then feed the fill stations. A site with a decent air system may only need to run the compressor once in the morning to fill the air bank which might last all day.