Because Im a powerlifter. Powerlifters need calories and Soy milk + my protein powder tastes good but my protein powder with water tastes like gasoline (and soy milk has more calories too).
I used to do soy protein + water and it was pretty bad but I could handle it. I recently switched to Beef and Egg protein from Soy protein and it tastes amazing in chocolate soy milk.
When you can't eat cheese, most desserts, pizza, and anything with a questionable production practice ("did my food share a surface with a milk product?"), and much more, you eat things without a lot of taste. I like Soy milk because it tastes good and keeps me sane while getting me my calories.
I used to do soy protein + water and it was pretty bad but I could handle it. I recently switched to Beef and Egg protein from Soy protein and it tastes amazing in chocolate soy milk.
When you can't eat cheese, most desserts, pizza, and anything with a questionable production practice ("did my food share a surface with a milk product?"), and much more, you eat things without a lot of taste. I like Soy milk because it tastes good and keeps me sane while getting me my calories.