I think that any responsible person in this day and age would want to make sure they pointed this out. Sure it really is the "buyers" responsibility to make sure they don't eat anything they shouldn't, but that does not mean that the preparer needs to make it difficult for them. Nut allergies are very serious and can and do result in death. How hard it is to point out that nuts were used?
OK I am off my soapbox
"
Most restaurants do describe dishes in their menus, GB, and they work really hard to ensure nothing slips by. The caveat is that sometimes situations do happen, like something getting processed in a food processor that has just ground nuts in it w/o being cleaned - not everyone in the kitchen is a food scientist!
When I was doing a lot of catering, I always asked the client as I was making up the menu, if anyone had allergies, and to what. We then tried to work around those, or make sure the guest knew which dishes had foods in them they shouldn't eat.
I agree with you - it is a serious issue - but if food preparers do what they can, outside of describing on menus, trying to keep other foods away from allergen causing foods, then it is ultimately up to the person with the allergies to ascertain if they can eat something or not. If you're in a restaurant, the chef or manager is always available to ask questions, and at most catering events, (unless it's a 'drop off'), the caterer or staff will also be on site to answer questions.
The flip side of kitchen irresponsibility is customer irresponsibility. I was catering a 300 person wedding reception, food was waaay over the top - one of the things they had set up was a $3000 raw bar it was totally awesome. Well, one of the guests had a shellfish allergy - KNEW he had a shellfish allergy, but 'just couldn't resist' sampling a shrimp. He ended up with a severe anaphalactic reaction, EMS was summoned and he went to the hospital unconscious. Ruined the entire reception for everyone. Should the server have refused to serve him the shrimp? Don't think so!
PS - Edited to say I'd be interested to hear IC's comments re the issue!