I agree with you, however you don't need to prove anything to anyone, remember it's just a game (and a very hungry one).
People who spend £5k on every Trove, there is only two option: or they are fre@king rich IRL, or they are just pathetic, bank account in the red, or eat pasta most of the time... Trust me I've seen some goodies like that... Nothing to be proud of. I've also seen on Reddit a dude spent his last saving for the current Trove in order to get the Kimono Costume... Pathetic.
Concerning the Unity, I am a returning player since about 2 months so I have no idea of when they implanted this system, but one day they will add Legendary Stones anyway and you will have to spend much more for it. And if they don't plan on add them soon, you have more time to gather Heroic Stone...