Here’s a perspective you might not have thought of. Younger person is already shamed for even buying condoms (the cashier will see them after all) so they steal the condoms instead of buying them. Store owners are sick of losing money so they naturally lock them up. So yes, it does have something to do with crime.

I’m not here to argue about what you think store owners care about your sex life, I’m just pointing out that there is a valid reason you haven’t considered.