The additives in oils are designed to work at various temperatures. For example, antiwear additives are generally of two types, primary and secondary "zinc." An all-primary zinc system would only be appropriate for operation at high temperatures all the time, as in racing (er... maybe, since oil temperatures are usually well controlled) and in very heavy duty engines (diesels that run at 80% load and up all the time.) In practice, there is little need for an all-primary zinc system anymore since mixtures of the two cover any need, including racing. In US engine oil formulations, I would predict essentially all passenger car and diesel oils are mixed zincs.
Another story is an out-of-date one: detergent additives cause combustion chamber deposits. It used to be that racers would use aircraft engine oils because they had no "organo-metallic" additives. That was only because the high oil consumption rates they had would consume enough oil that yes, deposits would form and cause knock - a death spiral problem particularly in aircraft engines because they run at near full power and you can't hear it knock. However, even race engines don't generally consume that much oil any more, and also having detergents is a good idea, since they keep the ring land areas clean.
Lastly, unless you only drive on the track and always change your oil after every event, and rebuild (and clean up) your engine periodically, you will want all the other additives in "normal" oils, especially dispersants. They help keep all the gunk, the wear metal particles, water, and anything else suspended so that when you change your oil, all these things are drained out. If you don't have dispersants, it all settles inside the engine and accumulates.
From what I have seen in engine oil formulations, I would ask what is being *left out* of racing oils, not what *extra* is being put into racing oils.
Keep in mind many NASCAR engines are lubricated by unadulterated off-the-shelf oils and don't have any problems at all.
