WHY LIE

This airline is just getting worse. I checked in early and the staff at the counter booked me on the first row of seat. I am semi disabled walk (i can walk with a crutch. I always ask for an aisle seat. She had booked me in the middle and my husband on an aisle which is no biggie as we could swop. Get to the check in gate, the boarding clerk screams at me and says I can't sit there as this is an emergency exit. They have to change me but I must wait for everyone to board and then will find me a seat. I said because it is hard for me to get up (should I need to go to the toilet, I need an aisle seat). She then called someone else. All the time the check in boarding staff are shouting. Another man arrives says I must wait because everyone has paid for their seat and I must sit where he tells me to sit. I said, I have also paid for my seat and your staff at the baggage check in counter should know not to book me on that seat if it is an emergency exit. I had to sit and wait for everyone to get on the plane. The plane was full and the boarding clerks were so rude, screaming etc at passengers. Just awful. I did get an aisle seat further back but getting on the plane, the first row is not an emergency aisle. There are no emergency doors. What amazed me is that a young child (no older than 7) is sitting in my seat. What a joke!! Was I moved because someone wanted their child to sit next to them and just a made up story. Why lie and why treat a semi disable person different.