"Also, yoga teachers are not supposed to do it for money. Read up on how Gurukuls worked."
Yeah I suppose you'll want to practice guruseva instead -- work for your instructor, such as cleaning his restroom, cooking, or going to the street begging for money on his behalf. No thanks, as much a traditionalist that I can be wrt yoga, some things are better the modern/western way.
"Yoga removed from its spiritual context is just a kitschy low grade thing"
No, yoga can be an awesome practice removed from any religion/spirituality. There's support from that even in traditional practices and texts. And if you get all dogmatic about this, I think you're doing it wrong unless you're practicing yoga associated with some form of Hinduism (most mantras are Vedantic chants, etc.). Get off my atheistic yoga mat :))
But I agree with the general stupidity of many commercial yogas. For one thing, heated rooms are a no-no, yoga has a purist approach as a biological and self-sufficient practice so it doesn't use any artificial support: no weights, stands, Pilates balls, etc., the ONLY thing you need is your own body (not just for the physical exercises / asanas, but all practices including meditation).