How much freedom do you allow

in eating/dining habits? I'm going to tell you which of my children I'm talking about, because I think age makes a difference -

My 8yo picks at her food, and by "picking" I don't mean she messes around with it and doesn't eat much. I mean she *destroys* her food as she is eating it by picking it apart - taking itty bitty pieces off the bread or anything else that she can finger feed and putting each in her mouth. She also combines this with putting on way too much (IMHO - it's not just "a lot" it's overflowing) ketchup/mustard/whatever. It's messy, it's gross, by eating in such little bites she winds up making little "mouth noises" which drive me batty (I have a thing about eating sounds, so I don't know if I'm totally overboard here).

Sooooo, I've encouraged her gently to stop, talking about manners, etc. Nothing. Finally I did something I probably regret and threatened that if she doesn't stop she's going to be excused from that meal.

I don't know why this is so important to me but it is. I feel like a scrooge though, but it's just GROSS and I don't want her eating like that at my table! Just pick up the stupid sandwhich and eat it like everyone else over five does! Ugh, sorry for ranting - I do it here so I don't do it to her face.

OK, one more rant, and I'd really love an answer to this because the past few years of frustration here hinge on this - WHY don't my kids ever stop doing the things I tell them to stop doing????? When I was a kid, if you told me not to pick at my food like that because it wasn't good table manners, I would have NEVER DONE IT AGAIN. OK, maybe I would have forgotten, ONCE. But my children just go on doing all these things I've told them over and over (and over and OVER) not to do. Talking does nothing, punishing does nothing, ignoring does nothing.) Whaaaaah!

Now for my original question - would you allow this at your table in an 8yo? How much "freedom" do you allow your kids at the table for little quirky habits like wanting a TON ketchup or destroying a sandwich or whatever. Am I a total contol freak ogre, or just a normal mom wanting my children to grow up with manners??