it's very rare to see people behaving like this, I mean Bitcoin wasn't released yesterday, it's not new anymore to know that you need to wait to get your transaction in a block, why would anyone rush anyway? As I was reading through OP I detect that this could be the case, some is indeed trying to do fast transaction because they are robbing people.
There are quite a lot of things that some people who use Bitcoin do not know about the network, some people erroneously believe that Bitcoin transactions are instant, and they do not even know the average time between blocks. There is no way to be certain this was a bot, but even if we agree that it was, the person behind it should know that what they were doing is useless, because their transaction would have still been included in the next block, and constantly increasing the fees didn't help to speed things up.
Before anyone argues about volume of transactions being low on those alts, they should check Tether first.
Mind you that people hodl and use Bitcoin for a couple of reasons, such as decentralization, security and also to have full custody of their assets. Do you want to hodl tether that is centralized, can lose its peg or be frozen in any wallet you store it. I understand if you want to use it solely for payments when you want to, but hodling it means you are putting your trust in the issuers.