I've worked retail sales for the last few years. I've never worked retail before. I'm often amazed at what an asshole customer I've been all my life, and never realized it. Truly a case of standing "in another's shoes".
The positive effect it has had on me, how I treat others, is remarkable. The lesson, I guess, for anyone reading this is that a lot of "kind action" can derive just by refraining from, learning to refrain from, so much of the unconscious shitty action that we all do on a regular basis. (edited)