If you have a use for, and are enthusiastically using, each of your knives, they are tools and not toys. If you have more knives than reasons for having them, then maybe it's time to rethink a purchase.

Unless you have some psychological "shopping" problem or real budget concerns, keep looking for new finds and share them with your wife. Maybe she was just sad you didn't bring back anything fun for her. You can always sell your other knives or give them away if she's really worried about it.