Europe varies greatly, with by far the highest level of tolerance in Northern Europe (I'm Norwegian, and I didn't even know about lactose intolerance until I was in the 20's - it just wasn't something that became a subject until we were exposed to more immigrants as while it existed in Norway before that it was <5%), with lactose intolerance increasing to well above 20% in many other European countris.

In any case the advice to down vast quantities as milk isn't universally applicable anywhere.