Maude

Does not have time to hear about your bargain deals; she’s just here to buy groceries.
She doesn’t want to chat in line and her glasses help her avoid eye contact.
She sits alone on the bus for a reason; no, this seat’s not open.
People are antisocial for a reason.
Sometimes (oftentimes) those reasons are attached to deep-rooted anxieties, childhood traumas, and PTSD.
Post-traumatic stress syndrome is not a malady that affects only veterans.
PTSD sufferers are often domestic or psychological abuse survivors.
Antisocial behavior is also characteristic of people on the autism spectrum.
And "high functioning" people typically aren’t seen as autistic.
Mostly awareness of these issues will keep you informed when coming into contact with people like Maude.
Maude isn’t rude... she’s scared and she just needs her privacy respected.