There's a balance that needs to be struck between stereotyping and logic. Logic tells us that a 100 lb woman shouldn't be a warehouse worker. A 350 lb man shouldn't be an acrobat. However, an individual 100 lb woman might not be a good acrobat either, and a 350 lb man might not be able to lift a 100 lb object in a warehouse. You must profile based on a logical least common denominator. As it pertains to traffic stops and police harrassment, an 80 year old great grandmother of 16 can be carrying a gun, so everyone should be treated exactly the same way. As recent news has shown, an oriental looking man is just as likely to try to detonate a bomb in Time Square as a middle eastern man, and a white 20 something is just as likely to shoot a congresswoman as a russian 40 year old.
Profiling is dangerous, not only because of the violation of personal freedoms granted by our constitution, but also because it lets our guard down to potential dangers.