The duffel bag story

My wife's friend's friend lives in NYC and was asked two weeks ago to dog-sit for a family that she knew.
The family's dog was old and sick, and they didn't want to put it in a kennel for fear that it would die while they were away.
So, the girl came over to stay at the house and, two days in, the dog died.
She called the family - who were prepared for the upsetting news - and they told her to take the dog to the vet, who would take care of everything else.
It was a medium-sized dog (no word on exactly what kind) and she decided to load it into a duffel bag for the trip.
Now, this part I don't understand: she decided NOT to take a cab, but instead hauled the dead dog on the subway.
She toted it along, and when she exited the train she was having a little trouble carrying the bag.
A man approached her on the steps and asked if she needed help carrying it.
She was apprehensive, for the obvious reasons, but allowed him to help her.
They got to the top of the steps and he handed the bag back to her.
He said, "Damn, that's a heavy bag. What's in there?"
She did not want to say, "a dead dog," so she said that it was some computer equipment.
Bad choice, because he punched her in the gut and swiped the duffel bag.
He stole the dead dog.
She had to call the family to let them know that she was mugged for their old pet.

The story has no kicker, because we don't know what the man's reaction was when he opened up the duffel bag, but I'm sure it was priceless.

We figure the man, no doubt, took the bag to Chinatown to move the product. What else would he do with a dead dog?