EVE Workbench is a free tool brought you by EVE Online players for EVE Online players. We offer our tooling for free to you (and all the other visitors) to use, but as all other websites in the cloud its not free for us. But when we started we made it very clear to each other that we don't want a "paywall" to use our services and if someone wants to support us it should be because they like it!
So, if you really like EVE Workbench please consider to support us. This will motivate us even more to continue the development of this nice project.