I know, but the answer is the same: people do that, because it is possible.
But, this doesn't answer on
why they're doing it, or at least not accurately. Anything that is possible on the Bitcoin network can be answered same like. Why do people consolidate their outputs? Because it's possible. Why do they use SegWit? Because it's possible. Why do they run a full node? Because it's possible.
It is especially true in test networks, where coins are moved here and there, just to see if something is possible or not, or just for fun.
But, this isn't a test network. That's real, hard, globally-traded money. If they want to test something they can use the testnet. They must neither do it for fun. Advertising URLs is the best reason I can think of, which mustn't be effective.