They are paying for early access to Trump's posts.
The first post they received after this system was turned on, was Trump literally posting "GREEN CANDLES. BEAUTIFUL GREEN CANDLES!!!"
This is an informal stock market term for asset values having a good day (or good minute, for that matter), with stock movements measured on a "Candlestick chart". This is a... not an admission, but a brag, that this is in fact an insider trading service, and that people who follow this insider trading service are going to make a lot of money. This is Trump announcing that he has rigged the stock market and you need to buy in right this moment if you want to remain competitive.
I am cautiously optimistic about this in some ways? Historically, the one thing you do not do in America is touch the money. There's now a hundred trillion dollars of capital that have an incentive for the lights to go out in the White House and to turn back on with JD Vance in a different seat.