We don't seem to encounter this as much as in the past, but have certainly found it annoying, particularly since we may not actually consume much water with some meals.

It may sometimes be a matter of how you phrase the request. We've found that we seem to have better luck by saying something like, "Just plain iced water, please" -- nearly always gets us the desired outcome without a lot of fuss (except in places where reliability of municipal water is questionable for non-locals).

This is usually specifically in response to the usual "still or sparkling" query. YMMV.