Why wasn't I served?

I was in Northgate with my friend this morning & we decided to have some breakfast at Mugg & Bean. A waiter sat us down and dashed away without even asking if we need anything to drink or not. We never saw him again,we didn't even get to see his name. We sat there for more than 10 minutes,no one came to our table to take our orders. We eventually decided to leave and go somewhere else, funniest part;when we were leaving the manager says,'thank you so much guys'. By the door there were two waiters standing idly, they also said thank you...I asked them why is everyone saying thank you to us when we were not served? The guy just said,'I'm sorry about that'. Just to be clear(not that it's ever an excuse) it wasn't busy at all, there were 7 occupied tables. The restaurant was empty and there were two idle waiters by the door. I'm never going there again and I know it won't change the price of bread for Mugg and Bean...that's still ok...just disappointed I guess.