It's not just bored kids ... I think some people just think it their responsibility to critique (whether they know anything or not). Believe me, you need to get a little tougher skin if you want to sell retail.
I take a vendor booth to dogs shows. We make items from the artwork of a well known dog artist. Most folks love her designs and we have tons of repeat customers. Every so often, someone decides they have to TELL me to TELL the artist to fix this or that, because it just isn't right (mind you, they probably can't draw a stick dog). I'm always polite (though it's difficult sometimes). One day a lady spent twenty minutes lamb-basting one of our Doberman designs, saying we'd never sell that design (guess I'll have to recall the last hundred fifty shirts
)
The topper was a gentleman just walking past the booth one morning. He stops and looks at the designs. He asks who the artist is. THEN, he tells me that I should get a different line of art, because this stuff is so bad I'll never sell any of it! (At that time I'd already had the booth five years, the artist has been doing this for 20 years.) When my jaw drops open (cause I can't figure out how to respond), he gets 'kindly' and says he's only telling me that to help. I said, THANK YOU and turned away. As soon as he walked away, I looked at my son and said, 'I wonder who peed in his cornflakes this morning?'
Of course, different strokes for different folks. If it doesn't appeal to you, why not just pass on by and don't buy it.