Well they're not 'returning', they were never at that location to begin with because they're only a couple years old, and infact dairy cows breeds were largely bred into their existence by artificial selection, so you probably wouldn't have any of these if not for people..
This is kind of like if my cat got scared of the cows and went into the empty grazing fields and I argued that it returned to its land and that the cows existence had prevented it up until now..
