How much money will your wife be spending in town while you are fishing and how much will she spend with you going to town with her. Also is she testing you to see if you will choose to spend time with her in town or if you will stay and fish.

I offer to go with my wife to town and hope she tells me she was testing me and says she really does want to go to town by herself and wants me to have fun fishing. If I get that; she will not spend so much that is hurts.

Simple Cost benefit analysis.