What to Wear: Leggings as Pants

Is it okay to wear leggings as pants? The fashion world is quite divided on this. My short answer is, who cares? If you want to wear leggings as pants, then do it! But when it comes to my personal opinion, I think leggings are okay on very casual days as long as they are thick and sturdy (not flimsy and half see-through), and as long as they're worn with a longer top.

Here's how I'd wear leggings as pants. What do you think - yay or nay?