That happens now anyway. My branch of my extended family is fairly well-off relative to the other branches, and so my whole life I'm used to my parents being asked by their relatives for money/favors/etc. I'd guarantee they don't give out their actual salary information to their relatives, but it's obvious they're better off.

Knowing or not knowing the specific number doesn't change anything with regard to relatives/friends bothering you for money. People who know you see how you live, where you live, etc and know generally where things stand.