The less strong people the better. Who needs the competition...
The only person I have successfully gotten into strength training was my girlfriend, and I think that's mostly because I'm in the gym those three days anyway, whether she's there or not, and she likes to spend time with me. Getting stronger was more of a side benefit. She's nowhere near as engrossed in the subject as I am. All other friends and family are either plain uninterested, or prefer some other means of exercise.
I just toss it in like a hand-grenade and move on to another subject. After all, I really don't need to spend half an hour discussing someone else's ailments unless I'm being paid to do so. I've recently found that uploading a video of me pulling a heavy deadlift can often provide inspiration to the infirm and doubtful on the basis 'if you can, I can'.
Good point.