Tip: don't whine about people not upvoting you. They take that as a challenge.

If op allowed her card to be kept on file then she gave permission to charge the full tab to her card, not just what she personally ordered. That's how tab procedure works.

Not if she gave her card to the server into start a tab. If she did then she accepts the charges that were made by the table, not just what she ordered .

It's possible she didn't know there was shrimp in the food, or that somehow the food she ate came into contact with shrimp (i.e. The cooks touched shrimp and then her food without washing their hands.) So it's not necessarily her fault.

But if you've got that bad of an allergy, you need to tell the restaurant staff so they can let the chefs know...and you should ask for ingredients.

There's a chance she didn't know, really. My dad didn't used to be allergic to shellfish and now he gets pretty bad allergic reactions.

Maybe she didn't know she was allergic. She could have not came in contact with shrimp until this point, or just hadn't had such a severe/noticeable reaction before. My grandpa used to be fine with shrimp/seafood, but later in life he started getting severe reactions to it.

I've been able to eat crab my whole life and just this week I got severe hives and felt like it was getting difficult to breathe. I took Benadryl and it went away. Maybe she had her first reaction and didn't know there was shrimp or didn't care because up until then she could eat it.

Something similar happened to me, but with hazelnuts. I used to love them, and NEVER have had any allergies to ANYTHING. No one in my family does. But one day I grabbed some hazelnuts after not having them for a month and my throat swelled closed, my tongue too, and all the skin around my mouth and hands were on fire. I don't know what changed but it was very sudden and -I- could have NEVER imagined I'd be allergic to ANYTHING, never mind THIS allergic -AND- to something I love. Ugh.

I've had this happen as well, only at higher-end restaurants though. I had to stop using my card because I couldn't afford their greed, basically. One time I was told the transaction was denied, and it turned out it was denied because they put something extra on my card and went over my limit (I have a very low limit). They charged me $36 worth of dessert that I never ordered. They apologized of course and played it off as an "error", but it happened twice before at other places so I don't believe it was an accident.

I'd be asking for an itemised receipt as well so you can see what you are being charged for.