Huh? It makes more sense to use redirects for tracking than to fight it. Why would anyone use anonym.to instead of just turning off referer in the browser?
Because you don't always want someone to know you're talking about them - maybe you're 133t next-gen anonymous hax0rs. Or maybe your forum is "private" and "exclusive" and you have the audacity to believe anyone at all cares.
Of course, anyone who actually cares about infosec stuff would know better than to hand over this data to anonym.to.