Daniel: Mesilas Yesharim is not Halachah. It is a very good outlook on life and is (if you even read the entire Sefer) meant to be done in steps. So who are you to tell others where they’re holding by? Maybe they aren’t at Prishus yet?
Also, not one Orthodox Rabbi?? I guarantee you I can find you many, many Orthodox Rabbonim who think it’s ridiculous to tell others how to spend their money from an anonymous message board.