I wish you all the best! (no I don't)

Today I had the refreshing and wonderful experience of having a really fucking stupid patron.
This patron was beyond comprehension of stupidity.
Dumb to the point that I am surprised she remembers to breath.
Dumb to the point that I am amazed she has lasted this long.
Dumb to the point that I am at a loss of words to describe it to you.
(but not dumb enough to not know how to talk).
This woman came up to me on the desk and asked me if I could tell her what her SIN number is.
I asked a question to clarify, was she asking me what is a SIN number? Or was she asking me for her SIN number.
She was asking me for her SIN number, she wanted me to tell her to her off the top of my head. She asked the question like the answer would be obvious.
When I told her I did not know what her SIN number was she became agitated.
Could I look it up for her?
No. I don't have access to that kind of private government information.
Surely the library has that kind of information just floating around.
Actually we don't.
She became aggrieved when I could not give her the number. Then she wanted to know how she could get it. (please be aware that this woman was in her late 30's/early 40's)I directed her to the service ontario website, but warned her that she would need ID and other things to get her SIN number.
She gave me a dirty look as she left.
WTF?