Hm, this sounds like good way of thinking about it. I already use this principle, but I had not thought it to apply it to such cases.

To clarify, I think I may have been thinking about it in the form of "I'm not likely to interact with these people", rather than "I'm not likely to interact with these people again." (Which raises the question of what if you are likely to encounter them again because you often encounter them in the same place. I suppose this still falls under "one random person, their opinion doesn't matter"; it's just going to take a bit of training to make myself think of someone I can already identify as a random.)