The best teams will be rewarded in two ways. First, you have the astonishing prize money (to the left) that will be distributed among the six best teams in both disciplines. More over the two best teams will be rewarded with extra slots for their continent in the Global Final.
This means the two actually winning teams do not get a spot in the Global Finals themselves, but if for example MugNmouse places first and Team Roccat places second, Americas and Europe will get one extra slot that can be obtained in the Continental Finals. A Global Challenge does not in any way work as a qualifier to anything.