Hey, what do you think the other two clerks are doing while the one clerk is handling all the customers? They're surfing the web and responding to posts complaining that postal workers have nothing better to do than surf the web!
It certainly does seem that some of the 547,000 postal workers are employed to surf the net to rebut any commentary that is negative towards the post office.
Clerks ought to be be all business and all available whenever a queue begins to form. No gabbing about the weather while patrons wait. It should be what do you want to mail and do you need any stamps, thank you good bye next.