Please take no offense Jan. Your question is a good one and I believe that it has been discussed before. I know we've had a few ladies active on the forum in the past and I'm sure many would be interested to know what percentage of our members are.
"Female" is more of a classification than a title. Actually, and to your credit, your english was too correct.
Had this been in the "real" world a guy would probably attempt a bit of a flattering salutation when addressing a group of women for the first time. So the humour, if any, lay in the juxtaposition of the two approaches.
Please don't take it personally.