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.
Yes, let's get into some Catholic doctrine.
Has anyone brought up the phrase yet, "Unnecessary occasion of sin"?
A beach is an unnecessary occasion of sin. A grocery shop is a NECESSARY occasion of sin. We have to eat in order to live. We do not need to sunbathe or swim in order to live.
See the difference?The actual danger, or occasion of sin, could be the same. Heck, it could be WORSE at the grocery store in certain circuмstances (30 young, attractive women in shorts and immodest clothes at the grocery store vs. only 5 near-naked women a good distance away at the beach on a given Monday late morning) but it doesn't change one's clear, rational, Catholic judgment on the matter.
It's all a question of: is it necessary or not to be there?