So long as airstones aren't visible, I see nothing wrong with them.
I would rather have an airstone that's well placed than a powerhead creating algae spots every few days where the water hits the glass.
Bubbles do rise from the bottoms of bodies of water ya know, so bubbles, just like current, are natural as well.
Whatever, my fish love it - they always play in it at night
Do what you want man, it's your tank