Several days ago, I found myself in line at the groccery store.  In front of me were two ladies with maybe 15 items.  

The cashier quickly scanned through their items, sliding them along to a bagger at the end of the counter.  

The bagger was an elderly gentleman, placing each item carefully into a plastic bag.  His pace didn't match the cashier's, and soon, all three women were waiting on the bagger to finish.  The cashier, with a harried sigh, started grabbing items and putting them into bags, pushing them towards the women who were checking out.  Her impatience and that of the women in front of me was tangible.