I will never understand the workings of a spammer's mind.
You temporarily shat up a site, so what? Everything goes back to business as usual pretty much immediately after, unless you somehow managed to keep the spam going for a month or more.
Do they imagine themselves getting exaggerated, enraged reactions? If so why? Very few people actually get that upset over it, most everyone else just rolls their eyes and leaves for a day or two then checks back. Do they actually find spam funny? It's sure as hell not useful for anything else, unless they keep it up for a month like I said, then they can actually permanently fuck up a site's community, but spam rarely lasts longer than a few hours nowadays, much less weeks.
Maybe I'm just stupid and overthinking what is essentially the imageboard equivalent of a BR going HUEHUEHUEHUE in teamspeak while playing a video game.