Since the SBD peg is close to being restored, @burnpost will no longer set a beneficary of @null. Instead, rewards will be paid to @burnpost and handled by the bot (or in some exceptional cases manually) in accordance with the rules.
In particular, if SBD is trading for more than $1, any SBD rewards received will be used to buy STEEM for eventual burning, which results in a larger burn relative to the rewards paid out. For example, if SBD is trading at $2 and STEEM is trading at 0.20 then immediate burn (or convert and burn) of 1 SBD would result in 5 STEEM being burned from the total supply, but using the 1 SBD to buy STEEM will result in 10 STEEM being burned. The latter also helps stabilize the price of SBD toward $1 by selling it on the liquid market, as well as contributing buying pressure to STEEM.
100% beneficiary to @burnpost