This.
She phrased it a bit strangely, but there's a difference in
"Do you know just how much wine you drink?" In isolation and "Do you know just how much wine you drink, buying the bottle could be cheaper"
One is more likely to be a judgement, the other is an attempt at customer service - saving the customer money.
Probably better if phrased "Do you know how much you will drink as buying the bottle might be cheaper?" Though I suspect that OP and a few others would still have had a problem with that and assumed that the bar staff/person was having a dig. I said in a previous post and I'll say again - most bar staff could not care less about your drinking habits unless there's a problem and they could be liable for serving you, you're really not that important that they'd give how much you drink and how often that much thought. She may have even said it and you misheard - and that's why your husband thinks you were rude.
But you, and many others have jumped straight to insisting she was judging and disapproving of you for what you drink - if she was disapproving, why offer you a bottle, which means you, as pointed out so many times, would actually be drinking more? It makes no sense.
And as she was helping out, so I assume not a regular member of staff, she maybe doesn't know you refuse the bottle each time. Service staff don't have a hive mind, new or infrequent staff may well ask regular customers questions they've been asked a hundred times, because they don't live behind the bar and automatically know each customers preference as soon as they look at them. Or they may be told to offer, regardless of how many times they've asked before, anyone ordering more than one glass or indicating they're staying a while where I work is offered the bottle on the strength of it being cheaper and then better for the pocket - and that's an expectation of customers that they get a good deal and value for money.
But service staff are often treated this way if a customer has a hang up about something or is having a bad day, we all know we can take it out on them, and not have any comeback, and even get apologised to because 'The customer is always right' it doesn't matter if they're rude, unreasonable or downright abusive, because of that little saying, it validates just about any behaviour that the customer feels like exhibiting.