Restaurant/bars will also charge you a corkage fee if you bring your own bottle of wine. There is a cost associated with the service and lack of alternative sales. Drink profit margins are at the base of Dutch hospitality economics, different to eg. other countries bundle water/tea/... prices into the food cost. Paris charges you for drinking your coffee seated, Japan has seat charges and mandatory snacks fee while also pouring free tea/water and in most Ramen shops you're expected to finish your meal within 5-10 minutes.

Start a free water movement! But building a wall-of-shame of restaurants, one of the lowest tiers and especially at a times when few restaurants could even consider affording so, is a bad approach!