What is it?
Unneccassary reactions when eating (sweets).
Worst offenders?
There is a LOT. Not even my favorite anime
Macross Frontier is safe from this.
What makes it popular?
I'm putting my money on the cute factor. As this trope usually falls on female characters. Their facial expressions/reactions = Kyaaa!! = $$$$$
Reason for the hate?
I'm a girl who loves delicious food...especially when it's sweets. I don't know, I just find the whole 'cupping-cheeks-and closing-eyes-while-going-mmmmmmnnnn!!!' frankly stupid. Hell, not even children do that. Not even the girliest of girl friends I have do that.
Is the hate worth it?
Well, it's just a personal peeve of mine. So it could just be me.