If your friends knew that you were rich or wealthy they probably would be asking to borrow money all the time. But the bad thing about it too is if you discuss finances with your friends, then your friends would also put a value on your friendship. And that is not something we want from our friends.
Moreover, if we have considered each other as friends, I think there is no need to tell them, they will know what kind of people we are through the way we dress, eat and spend in our daily lives. And hiding it from them is impossible and does not bring any benefit. Like us, i have a group of friends more than 10 people and we always drink coffee every morning or get together on weekends. Although we never explicitly state how much money each person has, it's not hard to find out if we want to but we don't mind that because we play together because we get along, not for money.