If I felt like I had to hide things from my wife, we truly have much bigger problems than how she feels about fishing.
As the soul bread winner of our house, I make every dollar that my family has, but none of it is mine. It belongs to my family. That is quite a responsibility, and I do not take it lightly.
On rare occasion I will buy something for myself, or my wife, or even rarer still I'll just give my wife a bunch of cash and tell her to spend it any way she wishes (usually on our 2 girls).
I don't believe my wife dislikes that I have a hobby that I enjoy. I always keep my love for bass fishing in the right box. Very rarely will I go fishing when there is something I can, or need to do with the family. This isn't imposed upon me by my wife, I impose it on myself (reluctantly sometimes).
I'm not saying this is the only right way, but I intentionally don't do things that would make my wife, or girls feel like they have to compete for me. As long as everyone involved has healthy expectations, it works pretty well for us.