A local woman was almost killed by a Starbucks dessert last year. Here's the story at the CBC website: "Near-fatal allergic reaction caused by Starbucks dessert".
And the worst part of the story: Starbucks didn't change the labelling on the product (subcontracted from another producer) and seemed reluctant to provide incident reports to the local health authorities.
Don't read the comments if you've got allergic kids. There's a whole lot of blame-the-victim in the comments, and several more comments along the line of "bring your own food if you're allergic."
One of my friends has severe food allergies and went out to a local allergy support group once. She commented that a lot of people in that group seemed to never go out anywhere. It's a classic Fear of Food situation, and I sometimes end up in that camp, worried for my kids, and freaked out that something random in their food will kill them.