Pets are the most pampered members of the animal kingdom today.
Even in earlier times, people had pets, buy they usually did not get to enjoy a completely free ride and a carefree life. Horses had to do backbreaking work, dogs were used in hunting, shepherding, pulling sleds, cats had to hunt rodents, pigeons had to deliver mail and many other animals could simply be turned into meat one day.
The Industrial Revolution followed by urbanisation has relieved pet animals of most of their former duties and simply turned them into pure pets or companion animals.
Life has become so dreary and disconnected for modern humans that simply having a pet can improve one's emotional well-being.
The current Pope even lamented (quite foolishly!) that couples were "selfishly" choosing to adopt cats and dogs instead of having kids