I get that it sucks having the sites we work on take a 40-50% cut, but you also have to understand the cost it takes to run an adult site. Payment processors alone count for a decent amount of the percentage they take. It cost money to process credit/debit cards. No matter the business, companies have to pay a percentage of every single card transaction. Ever gone to a bar or convenience store and there’s a minimum amount for debit/credit transactions? That’s why. Adult sites are considered high risk, due to the amount of chargebacks and such, so they have higher processing fees.
It also costs money to keep a site fully functional so thousands of models can stream at any given time. Then there’s employee costs, taxes, etc.
Also, most “fans” are more concerned about getting the most bang for their buck. Which they think they can get if they pay offsite. Rest assured, it’s rarely because they care about you getting more money.
Anyway, the best thing to do in this industry is to always always read the TOS of any site you work on or want to do work transactions on. If you have a hard time navigating a lengthy TOS Ctrl+F is your friend. You can also ask here, since most of the active verified models here have been in the industry for years and years and are well acquainted with the TOS of most sites.
ETA: Forgot to touch on the taxes part. Yeah, taxes suck. I’m very libertarian when it comes to my stance on taxation. However, another huge reason that these payment apps don’t allow digital sex service payments (aside from the general public just disliking sex workers and there being an increased risk of chargebacks/payment disputes) is that you’re not getting a 1099 from your personal PayPal account. They’re not required to report income information to the government/tax agencies like adult sites are. And you best believe if there’s one thing the government is always going to do, it’s take whatever money they can from you.