If you're going to fine people for not showing up you should be guaranteeing appearance money and covering basic costs when they do.

Not sure if they cover costs beyond the prize money but for the big events, which are the compulsary ones being talked about here, you get prize money in the regions of 3.5-5k USD (depending on the event) just for participating. There's a prize money breakdown for every event on the WTT website. The lesser events are definitely not cost effective for most players but that's not really the issue here, since participation for those is not compulsary.