You only pay whatever you set your fixed monthly total Kachingle subscription to be (say $10). The number of visits just allocates what percentage of that fee

You only pay whatever you set your fixed monthly total Kachingle subscription to be (say $10). The number of visits just allocates what percentage of that fee goes where. The idea is that once you decide to support a site, you don't have to think about how to divvy up your support; it's based on your usage patterns.