Vegan Food Production

I have recently been slightly confused on whether some products are vegan or not.  Some products claim to be vegan but are made in a factory that uses milk, so they say it may contain traces of milk.  And some products have the right ingredients but because they may contain milk traces they say it is not vegan.  Two examples spring to mind.

Example One
Cadburys “Frys Peppermint Cream”,  the ingredients are fine, no dairy, egg or animal ingredients,  but they say it is not suitable for vegans because it is produced in a factory that uses milk in production so it may contain milk traces.

Example Two
Animal Aid Chocolates are Vegan Society Approved but the packaging does say may contain milk traces.

They seem to have the same issue with milk traces,  so are they both vegan or are they not vegan?  Would the Vegan Society Approve of both productions of chocolate?

Of course the only way to be sure is to only buy vegan food that is made in a vegan factory but lets face it, there are not many of those around.

The EU now has regulation that we have to label food for allergy sufferers so if there is any chance of nuts or dairy then they have to tell you on the packaging.

From the Food Standards Agency

The rules for pre-packed foods establish a list of 14 food allergens, which have to be indicated by reference to the source allergen whenever they, or ingredients made from them, are used at any level in pre-packed foods, including alcoholic drinks. The list consists of cereals containing gluten, crustaceans, molluscs, eggs, fish, peanuts, nuts, soybeans, milk, celery, mustard, sesame, lupin and sulphur dioxide at levels above 10mg/kg, or 10 mg/litre, expressed as SO₂.

I am not sure how I feel about the possibility of traces of milk in my food,  but I imagine for some it is not acceptable.  But if for example the ingredients say may contain traces of meat, I would run a mile.

Where is the line?