Bad experience of counter service

Car conditions were good. However, service of the counter staff was beyond satisfactory. There was only one staff at the counter. He was working on another customer ahead of us but was too slow. My family was were forced to wait more than 30 minutes outside in rain. After 30 minute waiting I was told to show UK driver’s license and passport, which was ok. However, I was also told to provide the National Insurance number of the UK, which I had never been told to provide in advance as necessary documents. For foreign residents in the UK like me as expats, had never been aware of such number. I was struggling to get the number on line from the government website but couldn’t get it after all. It took another 30 minutes and he finally managed somehow without the number. I was so anxious about not to be able to rent car without the number whereas he was trying to manage situation. I often rent car in other EU countries but never had such bad treatment and long waiting before. It really annoyed me at the beginning of our holiday.