Do you see anything suspicious about this
thread? Apparently, most of the users registered on the same day, almost exactly the same time. And they all choose to reply to this specific thread with some random "interesting, well done, useful, thank you" type unnecessary comment. Their usernames are also of similar pattern. It looked liked possible alt accounts.
If you look closely well, you will see that this kind of users are the ones that always go after bounties because the requirements for bounties post are lesser, most of them are doing this for them to be able to participate in such, but just as you have suspected, it's likely that they all belong to a single person and if so, such could be termed as spamming and post bursting as well using multiple accounts, i wonder what this forum would have turned to if these people were allowed with freedom of doing what they want.