Do You Think of Yoga as an Intense Workout?

I'm beginning to get the feeling that a lot of people don't consider yoga a serious workout. Both colleagues and friends have shared this sentiment with me; one was even shocked at feeling hungry after an hour-long class:

Her: I don't get why I'm so hungry, I just had lunch.
Me: Because you just worked out for an hour!
Her: (whispering) But it was yoga — I don't know if I consider that a workout.

These people have definitely never taken a Vinyasa flow class like mine — my heart is pounding throughout the class and I'm drenched in sweat. I'm also the right amount of sore by the next day. Still, the idea of yoga not being a serious workout perseveres. As a friend of mine says: "I want more sweat, less stretch, and no chant." How about you?