Another issue I have with a mandatory ( non opt out) multiple beneficiary payout is that companies can and most definetely will censor content that was published outside of their website in order to force them to pay the site comission. This feature gives way too much power to corporations and is not in the spirit of steem unless it is OPT IN-OUT ofc.
Sorry to "spam you" but this is important matter. I don't want you to miss it.
It is entirely opt-in, service providers don't have to process your transactions or display your content. The provider who displays everyone else's posts will have the most readers and ultimately the most people using their API and therefore consenting to fees.