Mini tubs and tubbing developed as a result of the drag racing classes requiring that bodywork remained standard looking ..no flares. Aerodynamic efficiency is also a factor in the super quick pro stock classes. Tubbing has become popular as a "look" as well. I find it a little amusing seeing cars cars built to the "look" with massive rubber at the back and skinny 3" wide frontrunners squealing around the local cruise spots..I like the look too but I'd rather have a toy that was comfortable to drive and went round corners as well as it did down a strip..