Walking the dog with Rufus

So there I was, outside the Continental Cafe, enjoying a fine cup of drip and opening up the paper to gingerly peruse the apartment ads (anybody with any hot tips, PLEASE let me know). Just as I open the paper, I hear a crash, and sure enough, there's a cute little dog tipping over a garbage can and eating from inside. Smart dog. Hungry dog.
A minute later, the dog is panting at my feet. I reach down to scratch behind its ears. It looks unwashed, unbrushed, lost and confused. Or maybe I was just projecting.
I look around, there's no one in sight who seems to belong to the dog. So I check his tags, there's a phone number and an address. And his name: Rufus.
So I pull out my phone and call the number. Answering machine. I leave a message, including my name and number, and explain that I've found Rufus wandering along Commercial Drive eating garbage.
I think about going over the apartment listings and enjoying my coffee, but I don't want to chance Rufus wandering off, especially not in the often frenzied Commercial Drive traffic. So after a few minutes of deliberation, I finally tuck the paper under my arm and call Rufus to follow me. The address on his tag is only a few blocks away, so I'm really not going too far out of my way.
Rufus lollygags behind me, walking pretty slow. Oh, he must be famished and weak, I think. Poor thing.
When we reach the street that Rufus lives on, the dog picks up the pace, and bounds up the front steps to his gate. I open the gate, let him, and then securely lock the gate and leave, waving so long.
Feeling mighty proud of the good deed I'd just done, I head back up Commercial to Broadway, pick up another coffee and a muffee at J.J. Bean, and get on the bus. Most of the places I want to look at today are around B'way and Main, so I might as well situate myself there.
Just as the bus is pulling away from the SkyTrain station, there's a buzzing in my pocket. I didn't recognize the number on the phone, so I hoped one of the places I'd looked at in the last week was calling to tell me I could move in. Ha, fat chance.
"Are you the fellow who found Rufus?"
"Yes, did he stay in the yard where I left him."
"Oh, yes, but you see, I was at Continental with him. He's sort of a regular there. I like to let him off his leash and go romp around in the back alley."
"Oh no! I'm so sorry. I saw him eating out of the garbage..."
"Well, I appreciate your concern, but if you should see him there again-"
"I'll let him be. I'm awfully sorry."

So, I don't know. My intentions were true. My concern was well-founded. Nothing disastrous happened. What's the lesson here?