The whole thing where they collect money on behalf of someone who may not have an account and may be completely unaware of it seems unethical. It reminded me of a similar snafu with a project called tip4commit, which allows users to give bitcoin to projects they like. It also collected the money for any project on github, without an opt-in (or even an opt-out) mechanism for the project maintainers. Here's the issue where a lot of this got brought up: https://github.com/tip4commit/tip4commit/issues/127