This can range anywhere from:
- a smirk
- look of disapproval
- look of "omg you're creepy"
You're buying a birth control product of some form - along with other items, to make it seem like that's not the only thing you're buying. Doesn't matter though. You get that "look". Usually(but not always), it's a female cashier, between 35+ years of age.
IMO, a cashier is supposed to be doing no more than merely processing all your purchases, completing the transaction, and maybe bagging your items. A cashier should NOT be shaming you no matter what it is you're buying.
Personally I just shrug off the "look" and carry on with my day. And maybe save it for a funny bar story with friends. But there are people who find this experience much more offensive, and are tempted to at least do something, eg. let the store manager know, file a complaint, etc.
What would you guys do? Crack a witty remark? Say "problem, lady?"