Is it dangerous to mix hazelnut coffees with normal coffees in stores?

I think unless they very clearly show that this coffee contains nuts it is irresponsible. As you say someone with a nut allergy could have real problems. I agree with your concerns.

One of my friends is seriously allergic to tree nuts and has had bad reactions to just this kind of thing. Fortunately the mix was diluted enough that an Epi-pen did the trick and the hospital trip was avoided, but one good lawsuit and they could lose their business. Probably not worth it.

They should at least warn people that there are nuts in there. They could seriously endanger someone or get sued. For your part, why don’t you review them online and point out that they do that? You can post a review on yelp.com. If you really want people to know about it, get in touch with your local alternative paper if you have one. That’s just the kind of thing they’d go for. It’s local, it’s a “scoop,” and it affects the community. All the press will either force the coffee place to change their ways, or will at least alert the public to the danger.

One of my good friends is seriously allergic to tree nuts and has ended up in the emergency room because of it, despite the fact that she is ridiculously attentive to reading labels and not going near any kind of nuts.

It is horribly (and probably legally) irresponsible to pass off coffee as NOT having any nuts in it, when it clearly does.

I would leave the hazelnut coffee out of the bunch.

Most coffee places I know have separate grinders for flavored and non-flavored coffees. Maybe yours can institute a similar policy regarding coffee leftovers. That way, people with allergies to tree nuts can avoid the “flavored” blend of the day.

While there is no danger in simply mixing them and brewing them, there can be if they say there is no nut content.
Sadly the onus is on the person with an allergy as you mention. Many places in the US are now making legislation to label served items.

…I see signs all OVER the place in restaurants and fast food places warning of “shell fish” products and peanuts. .... I’m glad I don’t have any allergies ‘cuz I guess I’d just starve to death.

Yes it can be dangerous to the people who unsuspecting would not realize that it had nuts as an ingredient.