Mad? Me?

I popped into town this morning and parked in the multi-story car park. It's one of those where you pay before you return to your car so i put my ticket in the machine and it spat it back out with the message 'cannot read ticket'! I tried a few more times but the same thing happened so i pressed the red 'call for assistance' button. A woman's voice came out of the machine so i told her the problem and she said she would issue another ticket and talked me through the procedure. I put my money in the machine and a new ticket popped out. As i took it i said 'thankyou' to the lady who had helped me but she did not reply and as i turned i realised that the people who had just approached the ticket machine must have thought i was everso slightly mad thanking a machine!