This is because all water-based materials have been removed and replaced with bake & cake friendly oils; these oils mix through much better than water-based gels (which we know water repels from the oils in your baking).
Edible Food Colouring Mill Violet Oil Based 20ml Cake Decorating Sugarcraft
Colour Mill Violet - Oil Based Food Colouring (20ml - 100ml)
Colour Mill Oil Blend Food Colouring Violet: Next Generation Oil Based Food Colours - 20 ml
Colour Mill Violet - Next Generation Oil Based Food Colouring for Baking, Decorating, Icing and Cooking Food Dye DIY Slime and Crafts - 20 ml
The Baked Studio Colour Mill Oil Based Food Colouring Gift Set - Tiffany Violet Fuchsia Hot Pink Cany Peach - Buttercream Fondant Sugarpaste Icing and Chocolate Colour (Fairytale), 120ml
Oil Based Food Colouring for Chocolate - Vibrant Fat Soluble Food Colouring for Candy Melts, Baking, Cake Decorating - Upgraded Edible Food Colour Dye for Icing, Fondant, DIY Crafts - 60ml (Violet)