Most of the brokers whos clients dont have insurred accounts trade against their clients. they can whatever swap they want because they never went on the open market to buy/sell your positions.
I spoke to my (insured) broker who did charge me few times for the EUR/CHF swap nice chunk of $ I would say 7-8 times in the last 120 days). they said on some days they simply cant buy currency for swap in my favour so they have to charge me. I checked the story with another (insured) broker who told me basically the same thing. They were able to pay + swap on EUR/CHF but they had porblem with AUD/CHF so they charged their clients for that swap.