Because your yoga studio isn’t exactly sanitary.
Throw some vinegar in the wash with your stinky clothes.
It'll help get rid of that sweaty funk. From here.
DIY some spray to wipe down your yoga mat.
Also works on other equipment, like those giant bouncy balls. Here are a couple of good recipes.
Or make your own cleaning wipes.
Use them to wipe down gym equipment after you're done sweating all over it (if your gym's okay with that). This is a nice DIY.