Fanboy's Annoyance List blocks Flattr buttons properly. However, on flattr.com itself, those buttons are vital to the site's core functionality. I don't think that somebody purposefully visiting Flattr would consider the Donate button there an annoyance.
An example for a page where the button is blocked and the site rendered useless: https://flattr.com/thing/139913
I suspect there's no easy technical solution for this, but I would like to have it discussed anyway.
flattr.com
I'm not against the donation thing, I'm against the questionable js and the buttons being used.