[MaximumYComb]

A lot of them are fortified with nutrients that are lacking from a vegan diet, i.e. B12, D, etc. I don't think the nutrients in them are meant for most people but are meant for a certain demographic who consumes this product.

[TrisMcC]

Vitamin D is lacking in all diets. The only meat that has any measurable D is some fish but one cannot maintain an optimal level on fish alone.

Dairy milk is commonly fortified with Vitamin D. Some mushrooms, if left in the sun, also have vitamin D.

Vitamin D comes from the sun.

[consp]

You could try free roaming chicken eggs if you do not prefer fish or mushrooms. The yolk contains quite some vitamin D.

[htor]

but, there is no harm in getting an extra b12 dose for meat consumers as well! plant-based milks are not meant only for plant-eaters (to put it simply) they are of course meant for everyone