Either it was his first flight ever, or he was incapable of reading even the post transparent of situations. She responded by saying "why don't you just see if there is an open space over your seat"? She said this in nice, thoughtful, "reaching out to be helpful" way, but in flight attendant speak, she said, "yeah, good luck on that one, pal".
Some people are just naive. Others are plain stupid. Others, like the guy passing me as I write this to gate check his bag, may be both.
Reading a situation in any event is helpful. When you are traveling, I can make all the difference in the world.