Problem with Royal Caribbean cruises?

You may or may not remember me mentioning before that one of the things I like to do after I've booked a cruise for someone is to give them a call when they get back from said cruise just to make sure they've had a good time and that nothing went wrong.
It's also useful in finding out what the different cruise lines are up to onboard and which lines are best recommended to different people.
I was making one of these calls today when my passenger highlighted what he thought was a major flaw with Royal Caribbean.
But what do you think..........?
He had booked onboard Royal Caribbeans Independence of the Seas and was cruising with his wife and 17 year old son.

The problem was his son......
His 17 year old son.....
He had tried going to the different kids clubs and activities organised by Royal Caribbean, (the son, not the Dad), but had found them too juvenile and in his words " full of teeny boppers". But when he had tried to hang out with his parents in the bars and clubs he had been refused entry, even if he was only drinking soft drinks as he wasn't 18 or 21.
For anyone that doesn't know Royal Caribbeans kids clubs are........

Fisher price 6-36 months, (parent supervision required)
Aqua tots - 18-36 months
Aquanaughts - 3-5 years
Explorers - 6-8 years
Voyages - 9-11 years
Navigators - 12-14 years
Guests - 15-17 years

Now I got into cruising well past the age of 17 I'm afraid so can't comment from personal experience but I do remember being 17 and the thought of being stuck in a kids club with a bunch of 15 year olds would have horrified me! 17 is just on the cusp of adulthood and that's how I'd of wanted to be treated.

I think the problem may stem from Royal Caribbean being an American cruise line; adulthood to them means 21 not 18 so there's a big gap there.

What do you think though?
Is this a problem on all American cruise ships? Obviously no one wants a situation where there are loads of 17 year olds hanging out in the night clubs but ask yourself this.....
Thinking back to when you were 17,would you have been happy in a kids club with kids two, three years younger than you? Or would of you wanted to be in the bars with your parents?

Happy cruising