Yes, with all the gamification, many of them can't quit. What the problem is that kids don't have much money to pay for anything. So, if you make a product for kids, make sure it is something their parents will pay for. Snapchat is not one of them.
This is so wrong at many levels. The reason why apps and companies are focussed in getting the 16-22 year olds are
1. They have very high power in changing their parents purchases.
2. Their word of mouth power is exponential compared to a guy who is 30 years old working in corporation.
3. 16-22 year olds are going to become 20-28 year olds in 4 years which is a real threat to facebook. This generation doesn't want to be part of Facebook.