Some people have other criteria to buying a car, emotional more often than not. For example, Ferrari's and Porsche's are known to a lot of common folk and associated with rich people, GTR - not so much. Also, different cars have different feel to driving them, different sound isolation, suspensions, seating position and road view, these tiny bits can be evaluated subconsciously even though you're after performance.

If I based my purchase only on performance I'd buy BMW S1000RR which performs just as well (albeit comes with less safety) than the other 3 and cost just a fraction!