The freemium cam sites concept is very popluar and succesful. The whole idea is that the viewers can pay a few tokens to check out what the camgirl has to offer. There can be many viewers at the same time. So if everybody chips in just a few tokens goals can be reached very easy. It's all about the amount of viewers, so don't expect to be one on one with the model.
For a customer it is cheap (or even free) to get to see a show. A lot of the visitors don't pay anything at all. However if you are not tipping, you can enjoy the show, but the camgirls will ignore your special request.