I only read about half of the posts in the thread so, if I'm repeating, please excuse the following....
Most likely the thief saw my prescription drug bottle sticking out of my gym bag….
Anything left in sight (purse, package, shopping bag,
gym bag with prescription drugs hanging out of it, any bag, etc) is a very strong temptation to a thief. You probably made yourself the most attractive prospect in the area by leaving stuff in sight. The gym bag w/the visible drugs would probably be a great lure for a sting operation.
For 15 years, I drove an '80 Delta 88 that eventually racked up 375,000+ before I sold it. It was brown with a blue front clip, had slightly dented bumpers, no hubcaps, a decayed vinyl roof and no headliner inside. It was definitely what one would a call a beater.
I could leave it unlocked in the worst neighborhoods and it wouldn't get a second glance. Whenever possible, I would always park it next to an attractive target and never once was it touched, even though a screwdriver would obviously unlock the trunk and one of the doors. No matter where I was, no one ever thought that there would be anything valuable in such a trashed car. They always passed it up for greener pastures.
A time at the mall with an ex:
"Put your bag behind the seat; someone'll steal it."
"It's ok, there's nothing they could use anyway. I have my stuff in my pocket."
"But they'll have to break my window to find that out. Hide your %#@()* bag."
The moral of this story: Don't make yourself appealing to a thief. Put your stuff out of sight, even if it's worthless. The thief doesn't know it's value until they're away from the scene. Also, if you can, park next to vehicles that are nicer and more expensive than yours and thus more attractive to a thief.