Bukkit

So, I'm trying to make it so none of my users can brew potions, but they've exploited this by simply putting hoppers under the brewing stand and then moved the potions over to dispensers with the hoppers. Clearly they're getting potions by brewing them (because it's impossible to pick them up), so I'd like to know if this setting does absolutely nothing or I've just set it up wrong. I already have the setting to ban brewing in the config set to enabled. Running PaperSpigot 1.15.2 and here's the config:

BrewingBanned:
- 373:*:Potion of Slow Falling:You can't obtain this item!:Item is restricted.
- 438:*:Splash Potion of Slow Falling:You can't obtain this item!:Item is restricted.
- 441:*:Lingering Potion of Slow Falling:You can't obtain this item!:Item is restricted.

Dead ass plugin lmao