How come dogs tend to stick with their own race or breed, but cats dont?

I noticed cats although fight and often cling if they look alike, some bond that are opposite breeds like a calico and orange cat example. Always together like clockwork out of a lot of outdoor cats.

Dogs I noticed pack based on breed. Almost racial profiling or familiarity??

Anyone notice this? 

I realize I could ask in dogs or cats. I might switch. Sections.