Dylan, in payroll, when we want to move money to lots of people at a time, we send a text file, or an excel spreadsheet, or even just take a printout to a processor or bank. There is no amount of activity (especially when the bank is charging a hefty fee for each wire) that would ever make a bank say, "Whoa there, that's too much, it's going to take us days/weeks to do all of this". They would jump on that shit like throwing fresh steak into a pack of hungry stray dogs.
Payroll's a very specific purpose, though, and you have a specific relationship with the recipients and probably have more than enough identifying information on your employees to satisfy KYC requirements. It's not the same for AML purposes as sending large amounts of money by wire to people in various locations throughout the world whom you're not paying for goods or services and about whom you have limited information. Banks can and do impose transaction limits on accounts, especially when your business and/or your customers are seen as "high risk".
If you look at the cases where banks and money transmitters have received large fines for non-compliance with AML/KYC requirements, they've always involved large volumes of wire transfers to and from overseas jurisdictions and inadequate verification of identity, origin of funds and destination of funds.
This is pretty much it. There are also some withdrawals which for various reasons need to be handled manually by us before being sent out, and there are only so many transactions that can be carried out by our staff in a given day.