Zack is the sterotypical bad boy, whose only lines apparantly are ones that are supposed to be stupid. A joke from one episode is:
Cody: Mom's birthday is on tuesday so what should we get her
Zack: Mom has a birthday?
Cody: Yes, and I think we should get her a necklace
Zack: What's a necklace?
Ok so most of the jokes are supposed to be that Zack is an idiot. While Cody is the sterotypical nerd.
The show is highly unrealistic and sends a message to kids that you can destroy as many things and cause as much trouble around a hotel or anywhere and you will always get away with it because your parents will always take bail you out.
If that show were real then Zack and Cody would be arrested for damaging property, disturbing the peace, and will possibly have to pay thousands of dollars in damages.
Zach would probably drop out of high-school, sell drugs, and then get arrested, and be put in death row. His last words would be "What is death row?".
Cody would probably be released on bail, and he would finish High-school but his bad-reputation and jail sentance would not allow him to attend any college. He would work at Mcdonalds and probably marry a prostitute.
London would probably end up like Paris Hilton or become poor when her father stops funding her. Maddy hopefully will have a good future.