I don't come up with prices for add-on content.. I also don't develop them. I know people who do tho, not just for little cash shop features. Best I can say is we really do not know what the process involved in getting that content to the Mogstation entails entirely. There is probably some Quality Assurance team that needs to be paid for their time, probably some animosity between certain members of the Quality Assurance team and whatever artists make stuff as well, leading to expenditures and some level of crony-ism involved that we are just not privy to. That's business.
I honestly feel like the chocobo carriage is overpriced for what is there. It's an already in-game asset that probably had some slight modifications made to it, whatever coding was needed to make it a useable mount happened, and recycled "chocobo mount" theme. To me, that isn't getting my 35.99 or whatever the cost is. On the flip side, I was all about that SDS fenrir.. loved the theme it plays as well, and that is like not recycled asset. It's a one seater, cost 29.99 and it is account wide as well. To me I feel like I got my USD worth out of that. I use it every time I log in. I use the regalia too, and I said when that came out I'd pay $30 to get that on an alt or the rest of my account.
Is the stuff over priced? That's subjective. I'm a guy with disposable income thankfully, I don't try to flaunt it. There are multiple glams that imo are just not worth it to me. I will not pay for them, for the cost. Maybe on a sale, but even still at like 33% off, I am like nah, I'll just pass. I can "afford" them, but I just reign back and say no not worth it. There is the vast majority of the little cash shop I feel this way about. And considering the few things I've bought, and how all over the spectrum of cost they were it just came down to what I judge was worth it to me.
I fantasia'd to miqo 1 time, and back to Lalafell, and I feel that fantasia's are insanely overpriced for what you get, not gonna buy another, and even if they go on sale, not ever going to buy one. Now a buy one get one free, eh maybe, but I also just enjoy being a smol.
I know my schpeel here is probably hitting off topic at points but what I mean to say is, judge the value of the item, and decide for yourself. There are things that are eh sorta kinda want them on the mogshop but at the same time, flopping down 10-15 bucks for them even if I have it to spend just prohibits my interest from making it a sale for them. If they want my money, they'll adapt, and sell cheaper. If not, I'll just be short glam.