Flew out of terminal 2A yesterday CDG/ORD. Didn't see the nude-o-scope (I went through the security lane closest to the hallway going to the Admirals Club). Laptop in bin, coat and (neck) scarf in bin, shoes on. No problem.
Hung out in the Admirals Club until boarding. At the gate, the same woman who had checked my ID at check-in was checking IDs again at the gate. When she looked at my passport she looked at the stickers on the back cover and said something like "These are from last year." I don't know what the stickers signify or why it was important that there was one from the prior year so I just shrugged my shoulders.
Halfway to the plane, there was another woman checking boarding passes. She looked at mine and directed me to the plane. Halfway there, she started calling to me and said she'd sent me in the wrong direction and I had to go through a bag search. There was a line of people waiting for the search but I don't think that everyone on the flight was being searched (I'm not positive about this).
When I was directed to the female security officer, I had to remove my shoes and scarf again. Then I was wanded (no alarm) AND patted down. She then directed me to unzip the compartments on my carryon, which I did. Then she asked me where my lighter was (!?). I showed her where I had my lighter and she told me I wasn't "authorized" to have it. I asked her since when and she said again that I wasn't "authorized." I again asked, since when am I not allowed to have a lighter and she told me since December. She then "flexed" my shoes and wanded them (but not the second pair in my carryon

), shook out my scarf and coat (but didn't check my coat pockets (rolleyes again). Then she pawed through the items in my carryon.
After all this, she took my lighter and asked one of her colleagues about it. He told her I was allowed one lighter in my carryon so I was allowed to keep it.
On my way to the plane, the man directing people to their individual searchers thanked me for my "compassion." I was completely exasperated by all of this and told him that he was certainly not welcome.
Other than wanting to report on this useless waste of time my questions are:
1. What is the significance of the stickers on the back of my passport? Should I remove them to avoid future problems?
2. How in the world would the woman searching my bags know I had a lighter since she hadn't looked in my bag yet so obviously hadn't seen my cigarettes?