Calling people by using “Mr” is giving them respect and it is not only used when we address higher ranked people in the world but it is also a kind gesture to an older person or a person you highly respect. it also can be used if you bump into someone while in a hurry as “sorry mister” and i cant help but feel sorry because your dumbass brain cant comprehend that also we do not call “goats” mister they are an animal but if you highly respect a goat you can use this gesture its your choice and its upto you.