"wrong gear" is a questionable term. I keep my "core bag/goody bag" assembled with basic ten essential/survival gear stufff, a lot of which has pretty broad application.

A recent example. On Super Tuesday I supervised a polling place and at one point i needed a bit of string to hang an item. the most convenient source was my goody bag, which had lengths of mason's twine, normally used to construct impromptu shelters or bivys. But here was another use in a distinctly urban situation. Duct tape is another classic example of a broadly useful, versatile item.

Definitely if you have time, you can fine tune the contents of a bag to become more suited to the situation.