bipolar attitude

As i work in town im regularly at mc donalds. When ever i go there people make one long line but there are three tills open. I already spoke to the staff and questioned them about it and they confidently told me if there are three tills open there should be three lines and if the line is empty i can go to the empty line. I even witnessed them tell the customers to stand in the li e of each till. today i went in and went to the empty till and the staff memeber said to wait in the one long line and i questioned her about it she said yes well the rules changed. But ive been always going there. it was dissapointing because she just called the next customer while i was speaking to her. extrememly pathetic i must say