Not only were you comfortable in the store (walking around, being curious about everything and everyone), but you were comfortable receiving treats from strangers (without growling at them, first..hehe).
You did avoid being petted by one of the workers after he gave you the treat...but that's ok.
We're getting there!
The company of your brother, Rusty, helped.
Here is some avoidance...
Here's some more avoidance, but interest in the treat...
YOU ARE GETTING THERE, ANTI-SOCIAL, GROWLING BEAR!!!