>Grocery stores with an attached Kosher butcher should have lots of
>dairy-free items available,

The unstated reason, for those who aren't familiar with the laws of
kashrut, is that keeping "Kosher" requires, among other things, a
separation of milk and meat. The biblical edict to not "boil a kid in
its mother's milk" is interpreted as having meals that involve meat
or meals that involve milk products, but never both in the same meal
(meals are separated by hours, so that you don't have both in your stomach).

While the rationale for keeping kosher are different from those
surrounding allergies (the ramifications of breaking dietary laws
versus the ramifications of eating something that makes you sick or
that might kill you), the need to know what's got milk in it is
common to both.

Foods labeled "pareve" (and there are several ways to indicate that),
have no milk in them (with some caveats) - these foods can be eaten
with milk meals or meat meals. Other things are labeled kosher-dairy
(or not, if it's obvious) and sometimes kosher-meat (ditto).

As the archives show, there are lots of little caveats (like ritual
purification might leave microscopic dairy in purified machinery),
the kosher labeling is likely the most reliable means of quickly
ascertaining whether something's got milk in it.

That said, there are many things labeled kosher-dairy that are made
without dairy ingredients that are effectively dairy-free. That's
typically done to allow more flexibility in the use or proximity of
machines that process foods with and without milk products. Depending
on the product and the degree of sensitivity, several foods labeled
kosher dairy might be ok. Our hair-trigger allergic son can eat many
things labeled kosher dairy without symptoms. We always test these
foods with greater care (Epipen and Benadryl available, ER nearby),
because we never know...