One of my business partners is a capital-S Spender; her favourite hobby is shopping.
I wasn't trying to convert her, but was just sort of explaining why I've been excited lately. We're equal partners, so we have the same income and similar tax arrangements, etc, and I just decided to go ahead and show her my spreadsheets.
She got VERY excited, so I did one for her. She had very (very) small additions to her RRSP and TFSA planned for this year, so I showed her what that would add up to. "Well, what if I put $2000 per month in my RRSP, instead?" Changed the number, showed her the result, watched her eyes go wide.
"So what if I did that every year?" It took five minutes to show her how soon she could be FI, and at the end she was entirely convinced of the glories of investing substantial chunks of one's take-home income.
(I don't think she's taking up biking soon, or ever, though.)
Have any of y'all converted people in your life by showing them the direct benefits of saving?