Being upset about Zen/Atow/Vatira on GM is silly
Seeing so many people upset about Vatira and Zen potentially leaving KC and Vitality and its ridiculous. Whether you are looking at it from a player or organization point of view, it makes complete sense.
From a player POV, you can make the comparison to both traditional professional sports and to just an everyday career.
Any athlete in a profession sport is looking for two things: money and accolades. Obviously outside of these there are things like culture, player treatment, etc that you take into account, but overall you are going to go where you
Make the most money
have the best shot at winning.
In this case, the best shot at winning for both Zen and Vatira is to join the same team with Atow. Zen and Vatira won FIFAE, Zen and Atow won 2v2 worlds and Vatira and Atow won a LAN this year. There genuinely is not a better teammate option for either player. Sure, they're are other similarly capable players: Rw9, Killerz, Dralii, etc. but they don't already have the established chemistry. When you look at the history of "super teams" usually what you see when they fall short of their expectations is play-style and chemistry not aligning, not because of individual talent: In this case that shouldn't be an issue.
There is no reason any of these players should take a pay cut for "loyalty". That is just a genuinely immature argument. Yes, you can be personally upset, but at the end of the day; its a business decision. Imagine you personally have a great job with a good company but another good company comes along and says "We'll give you 25% more money to do the exact same thing". Would you turn them down? Probably not.
From an organization POV, you are building a team with (probably) the 2 most popular players in the game, with Atow not being far behind. Look at this subreddit or twitter which are exploding with posts about this. The talent pool is incredibly high in Rocket League so regardless of who you sign, you're not guaranteed any major victories (though this will obviously increase the chances). You are still guaranteeing you are going to be the most watched and most followed organization, especially for newer fans, fans who just want to see the highest quality rocket league, and fans of individual players.
TL;DR: This makes sense. There is no reason the players should not do this.