Same, I only joined yesterday and at first couldn't get what a snipe is at all. Very weird phenomenon from an outsider's point of view.
It would never work on any other platform. Imagine complaining on YT / Insta etc. coz somebody made a video in your genre for example. Like noone would be allowed to make Minecraft videos because PewDiePie already made one and claimed the game to itself. Or saying "how dare Pepsi make soft drinks, Cola made them first" 🤓☝️
Competition is healthy and good for consumers. Nobody has exclusive rights to translate a series unless they have a contract with the publisher.
Don't you think that it's because you're new that you wouldn't understand why other people dislike it? There wouldn't be a term "snipe/sniping" in the manga community if the act is actually good.
There are tons of manga that aren't translated that they can translate instead over an already being worked on manga.
There are also cases before where the one doing higher quality translations gives a manga up because someone else did it in lower quality but earlier upload. Worst case scenario, the sniper would get lazy after and abandon it as well. Basically this is the reason how sniping got infamous.
Content creation isn't the best comparison at all as each creators will still have different styles and of course content while having the same game. In a manga once you've read a translation you'd most likely not read other translations of it again.
Welp, not that you should care. As long as there's a translation, it's fine I guess.