Who was it that said “every experience is a drugs related experience”? We are (bio)chemical machines that work with “drugs” for day to day processes like sleeping, emotions, etc.
All foods are “drugs” and we create a whole lot more from them internally. As long as one defines drug as “a chemical substance that has an effect on the body” about any substance could be made illegal. (Ever took fructose sweets (pills) while on a trip? You can feel the energy pop into your brain - and that’s the active ingredient in for example apples.)
When the definition slides away from “a chemical substance” to just “something that has an effect on the body” anything else also becomes a target: music, books, movies, colors, beauty, religion…