I agree that sarcasm, insults and overall rudeness is employed way too much on these shows.
However, the rest of the complaints are a bit muddled. The parents on Good Luck Charlie, for instance, are a big presence on the show and *always* catch their kids, doling out punishments for whatever they did wrong. In fact, it is a running theme that everyone is scared to cross the (pretty strict) mother. Also, the phenomenon of young girls thinking it is cool to act older than they are did NOT start with Disney or Nick. I'm in my 40s and everyone wanted to be older even then. And finally, some of the things that adults read as sexual barely register as such to the kids watching the shows. Long hair and lip gloss does not a vixen make. Sometimes we end up just projecting adult anxieties on kids.
Now I do agree some shows are so OTT (like perhaps Victorious, which was full of sexed up jokes, or Wizards of Waverly Place, whose protagonist was a habitual liar who constantly put down the "good" kids around her who had the nerve to have good grades and obey parents) but not all of these shows are cesspools of corruption. They are also not the only thing in the world your child does with their time, or the only media they consume. The right (age appropriate) show can be fine in a larger context, especially if you have a good dialog going with your children.