My father is an amazing salesman. He used to sell for Schwan's food in the 90's (those big yellow trucks that delivered frozen food to your door every 2 weeks).
He had a blind couple (husband and wife) that were on one of his routes, and they bought a little bit of food every time he came by. But they could never read the menu, because Schwan's only had printed brochures. One day, he had me and my siblings record on audio cassette the entire menu and their prices.
His sales from that couple shot through the roof! All of the sudden, there were all of these options for sale that they didn't even know about before, and now they wanted to try them. From that time forward, they were very faithful and consistent customers. And, of course, they were very appreciative of the gesture!
Every 6 months or so, when Schwan's updated their menu and/or pricing, we would re-record the menu, until Schwan's finally figured out an audio offering of their own.
A few years ago, my father ran into the couple when he happened to pass through their town (my father no longer sells for Schwan's, but now sells insurance and investments). The couple remembered and asked about each of us children by name, these decades later.
It's neat to see how just a little consideration (and a bit of extra work) can make a huge impact on someone else's life!