The answer is banning irresponsible parents. Banning the ads will not make those parents responsible. They'll just something else stupid.
How can a parent be not "equipped to deal with the onslaught". There were plenty of junk food ads when my kids were little, and there was one word for them when they asked...NO! It's that easy. They may not have liked it at the time, but they got over it. I think today's parents are too much into "being friends" with their kids, and not being able to say no. "Oh, it'll hurt their self esteem", as one parent told me. I almost choked...her. Saying no is the most important thing we can do for our kids.
Anyway, no I don't think banning ads will make a difference.
Great question, by the way.