Agreed. And for a lot of people, routinely being lied to by a spouse, especially about something as important as where joint funds (grocery money, for example) are going, would be a deal-breaker right there.
1. Happy Marriage = Joint bank account for household and "together" stuff and separate bank accounts for personal stuff.
2. Establish "general understanding" that you don't need to report every purchase made regarding your hobby; and your spouse doesn't need to report every purchase made concerning her hobby(ies). I don't think my wife wants to hear "Sooooo, how much did that pair of shoes set you back?"
3. Or, there's always: "I know, I got something fun; its your turn, what is it that you really want?"