A Not So Funny Occupied Property Experience ! Be Careful!

First just let me say that I personally dislike and I am uncomfortable at scheduling and showing occupied properties . I guess I will just have to get over it  or make sure I ask the listing agent all conceivable questions i.e  are their animals in the house, persons at home, recent communication if scheduling has changed. Anyway, Our buyers had requested to see this house  and so we went through all the procedures of calling the listing agent to coordinate scheduling. We arrived at the property with the buyers and all of a sudden we here dogs barking in the house. I mentioned to my wife that I don't think we should enter this place especially after first knocking on the door repeatedly and then waiting for about four minutes. Our buyers sort of looked rather puzzled. Surprisingly enough a little dog peaked his head out beneath the curtain. My wife opened the door in which I had reluctantly remarked , who in their right mind would leave their dogs at home without a sitter or? The house was definitely occupied with three little frightened little doggies. A strange emotion came over me that signaled that we were not alone and someone else was there. The buyer and my wife started there incline up the staircase and all of a sudden a door abruptly closes. I noticed that they quickly had walked back down the stairs. I inquired as to what had happened. They chuckled a little that their was someone smoking "weed". We all managed to leave safely and I started wonder all the "what if questions" , you know what they are? Anyway this man comes out the door about five minutes later and looks at us. I then mentioned that we were real estate agents and had been told that no one would be at home and it was ok to show the property. He said very little if anything. Perhaps he was somewhat buzzed? I' m sharing this story with you because there were stop lights that went on in mind in the beginning of this experience and I think if this ever happens to you that  you will consider rescheduling or at least call the listing agent back. Simply, who knows what would have happened if they had surprised this character? Even though there were four of us , unsuspected inhabitants should rattle anyone! What do you think? I ethically plan on speaking with this listing agent!