I know that an inflatable surfboard won't replace the real deal, but it can work in a pinch. Imagine trying to fit 4 buddies and 4 traditional surfboards in a small car, not happening.
Might be worth checking out the Thomas De Lussac Surf Air Inflatable Surfboard which rolls up to fit in a medium sized duffle bag. Or you could slow things down a bit with a inflatable stand-up paddleboard.