Yeah, $4.99 for a shoulder piece you can't even see on your character in game or $23.99 for a full set that you can't tell you have on is so much better than the League skins... Literally the only thing I ever bought or would consider buying in Dota 2 is/was the Compendium.
Wtf are you talking about? Have you ever even played dota?
First, all you get charged for is cosmetics...you get every fucking hero..and you dont have to buy them. And secondly, the hero sets (ie the arcana sets you are referring to) that cost an arm and a leg have unique animations, spell effects, spell icons, weapons and so forth and you can definitely tell it is on.
Take the Legion Commander arcana. It changes her from some good commander to an evil hellspawned bitch with different voices, going from a polearm to dual wielded swords, glowing eyes, smoking ambient effects etc.
The arcana for her is fucking incredible.
Same goes for say, for Phantom Assassin. The arcana looks fucking badass and even leaves markers on the map where she has fufilled assassinations on other heroes.....not to mention it changes her basic attack animations, stance animation etc ......and a badass effect goes off when she crits her enemies with her ultimate coup de grace. You are really misinformed. You get everything for free, and can support the game through means like the compendiums, weapon sets and such, but you get everything. I choose to buy the arcana and other cosmetic sets because 1) I can afford it, and 2) supports the game, and mostly for me, 3) because it creates revenue for the incredibly talented artists who can use their skills to make money from the community which have the means to support them. Its a win-win-win for everyone.