Well yeah, it's the kids decision but they aren't going to make a great short-term decision for a bad long-term decision. $ talks and is very important in the process, regardless of the whole "love the of the game" bs they'll tell you..
I don't think the shoe companies would want them playing "over there," when they could capitalize more from their rookie year in the NBA. These games in Europe aren't going to be watched for the most part besides basketball junkies.
You think their love for playing basketball is BS? That seems awfully jaded considering it's an 18-year old kid that has yet to (officially) make a single dime playing it.
I also think your view on Europe is a bit narrow-minded. Nike and Adidas are global companies....Adidas is HQ in Germany. Basketball is arguably the second most popular sport in Europe (just like in the US). Let's look at it from Nike's perspective....they buy the Andrew Wiggins hype that he is the next LeBron. They want to build a brand around him. Word is Adidas plans to make him a big offer once he's finished college. Putting them in the driver's seat is the fact that Wiggins' college team wears Adidas, so he will have an entire season to get comfortable with their product. Comfort level with shoes is a huge deal to basketball players. You are likely going to have to sell him big time to get him to switch.
You could offer him the same amount of money right now, and then get him a contract with one of your teams in Europe for a season. You can start building your brand with him, now. He can film commercials, now, for both Europe and the US. He's also marketing/wearing your gear in Europe, easily your #2 market in the world....as opposed to someone else in the US. He's on Europe's version of SportsCenter every night he plays.
From his perspective, he gets paid from Day 1. He doesn't have to sit in classrooms for a semester. He gets a taste of professional life before he gets to the NBA.
And he will still be a rookie whether he goes to college or Europe.
It's a very, very rare player for whom this scenario would make sense, from anyone's perspective. But for this one, I see it. And for Wiggins specifically, he's Canadian, so he's already used to life in a slightly different culture.