There is a shortage of Drowned-based items in Towny like nautilus shells and tridents. Hence, drowned spawners would be a great way to make those items more than extremely, extremely rare. Or maybe just sell tridents or nautilus shells in the vote crates. Either way, you can't just drown a zombie and have it drop tridents. Drowned zombies only drop zombie drops. So don't use that as an excuse. Thanks.