The Catholic spiritual life has this idea that you atone for your sins on earth. If you are presented with a difficult situation, you endure it to atone for your sins. You might even go so far as to choose to stand in the regular Wal-Mart line rather than go to the quick checkout line.
That's what the nuns were doing.
There’s atoning and then there’s atoning.
Waiting behind people who are buying for the next life as well as this one is not helping anyone.