Oh boy, this is going to end up lengthy. Bear with me
Upset? Not in the slightest - someone's comments on the don't have any more power to upset me than some random checker's (ie: none at all if I don't let them!).
I gave you advice, it wasn't what you want to hear. I acknowledged that, but I still firmly believe you will be happiest in the long run learning to give everyone, but especially random strangers, the very highest benefit of the doubt regarding their intentions. Your upset and annoyance is in your control - that's a very empowering thing!
You can control your response and feelings, and use that to feel better about this and other future situations, if only you choose a generous, charitable emotional response toward comments that might otherwise rub you the wrong way. Strike up a conversation about how/why you love the food she's commenting on, or share a recipe tip while she's bagging your stuff. Feel happy that you're such a regular customer you are familiar to the staff and that they take time from THEIR job to chat a little with you. There are so many ways to turn this around as a positive, but you must be intentional about choosing that sort of response instead of defensiveness or criticism/offense.
This is entirely under your control, that is the point I'm trying to get across. If you can figure it out in something as incidental and unimportant as a throwaway comment from a random employee at a store, you can apply it to more important relationships and interactionsm to your own benefit. It's really an excellent skill to exercise and master (and makes one an imminently more cheerful person to be around, I speak from experience!).
Addressing your last comment - You're reading too much into my comments above, and the wrong thing, too. That has been exactly my point - meaning and intent is something YOU (or me, whoever the hearer is) assigns. We do this based on our own experiences, feelings, prejudices and preconceptions. Much of it is unconscious. But we still do it, and can unknowingly damage our interactions with many people in our lives due to our inability to give them the benefit of the doubt and not read more into their comments than what they are on their face (or choose to take a seemingly incendiary comment in good spirits). I'm a random woman on the Internet, not someone responding emotionally or seeking to bait or belittle you. The very best way to take my comments (and the spirit they are intended, by the way) is as a well meaning stranger trying to offer good advice for feeling better about a situation while not escalating it - win/win. If you look at it that way, instead of reading intent and responding reactively, the entire thread changes tone and becomes beneficial and friendly instead of hostile or defensive. No matter WHAT my or someone else's intent may be, would YOU not be happier assuming the best than the worst?
That's the advice I would hope you and anyone else in a similar position would take away from this. Exactly what I said, no reading into it necessary