Localmonero/Agoradesk trader here.

Every payment method and country have its own market price. For an example central exchanges doesn't accept Paypal, Cashapp, gift cards, Cash at ATM etc. Most of them only accepts bank transfers. So you're comparing apples to oranges.

Even if you compare bank transfer offers you have to keep in your mind; some banks blacklist central exchange's bank details, so you can't make money transfer and/or it has much less strict KYC which is more privacy friendly.

Also you can benefit from OTC advantages like there's someone can help you directly and/or can offer custom solutions for you.

The market markers are taking huge risks, legally speaking and from scammers everyday (paypal method especially)

They're not that much more expensive. Have you been to a bitcoin ATM? You'll tell them to go fuck themselves with those kinds of prices.

What you're seeing on localmonero is the true price for p2p. Exchange prices are lower because of the bullshit you have to tolerate to use them, bank accounts, KYC etc. There's a premium on p2p monero because it is better.

The beautiful thing about open markets, in theory if somebody can provide a more efficient exchange service, they will compete on local monero and drive the prices closer to market.

Classic arbitrage incentives, so if somebody else can convert monero to Roblox bucks very efficiently they could undercut current providers of Roblox bucks. We just need enough market depth to get those participants to compete. And until that happens the high margins are what incentivizes people to provide liquidity in obscure markets.