Just wondering how most hobbyist that are very active keep the hobbying expenses hidden from the SO. I have seen over the years there are a variety of So's, some are not involved in the finances at all, and on the other end of the spectrum are the ones who audit every receipt and withdrawel. There may be some who have seperate accounts but that seems pretty hard to pull off. Just curious how most guys pull this off.

My wife and I have separate accounts and a joint account for common expenses, e.g., mortgage, utilities, etc.  I never question what she does with her separate account and she never questions me.  It works.