That's the risk we all take with using voting services: the payouts can be skewed if very high bids come in during any given voting round. It's not just @boomerang that this happens to. It's others as well.
The user that bid 181.481 SBD in that round actually lost money because it's clear as day on Steem Bot Tracker that the maximum profitable bid is far less than that for boomerang. See: https://steembottracker.com/
Perhaps a rule could be suggested across the board that all voting services accept no more than a certain amount of SBD or steem in any given round. For that to be implemented though, it would have to come from Steemit Inc and the Witnesses. Expecting everyone to abide by the same constraints is not realistic if they aren't enforced by the platform's internal mechanics.
For example, you've got the recent issue of Grumpy Cat pushing a 3.5 day maximum post age rule for bids. Some voting services are following it and others aren't. For those that choose not to, users that utilize them are at risk of being flagged by Grumpy Cat. As you can see, this poses a dilemma for voting services too, because Grumpy Cat arbitrarily set up this rule himself and is enforcing it because he has a lot of SP, even though it goes against the very framework of Steemit itself. These types of constraints need to come from the top down for them to be equitably applied to everyone.
Yes, we have to check bot traker, and wait until the end, otherwise there is this danger, but giving less than half of the vote purchased is not correct.
It doesn't happen to me very often, because I use the SteemBotTracker, but sometimes, monies have been refunded (whole or in part) because the service can't be rendered. That's simply decent, honest business. I understand there is a certain amount of risk with regards to more, or less, or even no profitability - but accepting considerably more than the bot's vote value and thus returning less than 50% of the stake as a vote is unreasonable and cheeky, to put it mildly.
I completely understand. And as a blogger that has used voting services here, I've had my fair share of experiences where my bid wasn't profitable because much larger bids happened to come in during the same round as me. I personally accepted it as the risk I take in using the services.
However, I think the more prevailing issue we have here is whales now setting arbitrary rules such as maximum post ages for voting services. The users have no way of knowing what the unspoken rules are on the platform - they simply know that votes can happen up to day seven. Voting services aren't mandated to operate by rules that steemit itself doesn't impart upon them. So it's now become an even more pronounced issue that necessitates intervention from the leadership of this community to ensure that everyone is working under equitable parameters.