Not only is that irresponsible, but could potentially be really dangerous. Having females in heat with several intact males around. I can just imagine the fights that could break out. Dogs (and people) could be seriously hurt.
Also, what if two males end up breeding one female during the same meetup...you wouldn't know who the father is..
Just dumb
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~Magnifique Yorkies~
Purchasing from backyard breeders, pet shops, and puppymills perpetuates the suffering of other dogs.
Educate yourself and buy from reputable breeders or rescue.