You apparently get annoyed very easily.
Well the bell is at a pretty grating pitch and decible level for me. But probably what causes the most irritation about the bell ringers is that for many they symbolize everything that's wrong about Christmas, with their traditional place in front of department stores that bell is the symbol of annoying crowds and crass commercialism because they stand at the border of all that during the Christmas shopping season. It's for a worthy cause, and I try to stick a buck in in the bucket periodically, but I can fully understand why they drive some people batty.