Well that might be your personal experience and opinion but I've seen plenty of people wearing all the vanity that's glamourable both on the server and on the DF. The people you don't see are probably because they couldn't obtain them in the first place, especially PS4 players who didn't even get a chance to do the events because that version launched on April 2014, so now they're screwed because the only way to get them is to buy them from the cash shop.
If that isn't a disadvantage I don't know what is. Why should they be punished, as minor of a punishment as you think not being able to get vanity in game is, because of their platform of choice? Why shouldn't a brand new player have a chance at getting those items in game, a player brand new to Final Fantasy even, who didn't follow the game at all? PS4 players that got the game around September this year or before that got the chance to get last year's swimsuits along with the 1.0 yukatas, so why just limit it to that event, even though past events also offered previous items? It wasn't even because it was the anniversary event, though admittedly it was included under that umbrella of events, but the actual anniversary event came out about a month later.
Around 5 or so seasonal events since launch had included previous 1.0 event items and even one event included 2.0 items all purchasable with gil, even if you didn't do those events in both 1.0 and 2.0, so why stop doing that just now after all this time? People keep saying they need the money, well they needed that money even more before ARR's launch, so why not straight up announce a cash shop at launch?. Why not clearly state that event items would be one off only, and would later be placed in the cash shop since the very start?
This is also a question that no one seems to answer, not even a simple "well it's their game so they do what they want and don't have to answer to anyone!" which would be a terrible response but would still be a response. "Well plans change" would also be a terrible response because why change their plans so late? They had less money before, so a cash shop would make more sense before when they needed those extra funds. So now that the game is successful and has 2.5 million adventurers they, understandably, want more money? But wait, didn't they have less money before than now, so why not launch with it in the first place? Doesn't make sense, or rather it does make plenty of sense business wise I guess, especially now that those 2.5 million adventures are potential cash shop buyers. If people do end up buying from it that is, bless their souls.