For any dietary scheme built on avoiding certain foods (vegetarian, vegan, gluten-free, keto, paelo etc), there is a thriving cottage industry of substitutes.
Some folk have an ethical objection to milk but want something that vaguely resembles it. For such people, whitened liquid cardboard -- soy juice -- is a popular alternative. Other people drink almond juice or rice juice.
Edit: and some people have allergies or intolerance to things in milk. I'm lactose intolerant, so I'm covered by lactose-free milk. But some people are genuinely intolerant of milk proteins etc.
I object to that characterization. I rather like the taste of plain, unsweetened soymilk. It fills a very different niche than milk, however; milk is thicker and heavier (unless it's skim crap), and I'll have it with dessert, while soymilk is lighter and more refreshing. But I don't drink either on a regular basis.
Some folk have an ethical objection to milk but want something that vaguely resembles it. For such people, whitened liquid cardboard -- soy juice -- is a popular alternative. Other people drink almond juice or rice juice.
Edit: and some people have allergies or intolerance to things in milk. I'm lactose intolerant, so I'm covered by lactose-free milk. But some people are genuinely intolerant of milk proteins etc.