Because you are intentionally bidding for upvotes using posts that have already been upvoted by @boomerang or have been upvoted by @spaminator (and you know you will be refunded) and then bidding for a new post at the same time (see @boomerang at 0:53 ET Oct 2 2021). @boomerang has an error and you receive the almost full upvote.
That is not the first time that you commit this fraud.
Next time you will be banished by @boomerang and other bidding bots.