Companies often share contact information with each other. I don't find it to be a big deal at all. If you were a....say plumber....and someone one of your customers (because that's what an MSC is) knew wanted a plumber, wouldn't you want them to give your name and number to them? It's the same thing. It's not like they gave them your bank account information.
If a shop normally pays $17 and has been raised to $35 then that's what Presto will reflect. It doesn't sound like the scheduler lied at all. Unless the shops are released at the beginning of the month at $35, but I'm guessing they're not.
I have only once asked to be deactivated from a company. That was simply because they had made it VERY clear they were never going to assign a single shop to me. My emails were repeatedly ignored but my request to be deactivated was replied to within 30 minutes. So I'm guessing I made the right decision there. There are companies that I currently will not work for. I have not asked to be removed because you never know when they will get a new owner/scheduler/manager/client.
There are reasons that a body stays in motion
At the moment only demons come to mind