My 21-year-old son recently accompanied me to the grocery store. Our list wasn't lengthy. We needed a few items for a cookout with neighbors: hot dogs, brats, buns, some fresh produce, and chicken. On these shared trips, the two of us have taken to playing a "Price is Right"-inspired guessing game. Who can correctly estimate the final total without going over? He's uncannily good at this game, beating me nearly every time, often guessing within a dollar.