Where does one draw the line then? Isn't immodesty all around us?
Isn't the line here obvious? I walk around a grocery store where there happen to be a few women wearing shorts or tight shirts, vs. I walk around a beach where nearly 100% of the people there are gravely immodest. In addition, going to buy groceries is a necessary activity, and it would not cause scandal for people to know that you were there, even if some present happened to be immodest.