I was looking at paxful and I can see a lot of people do this, but my question is how do the ones with a lot of volume get the money back into bitcoin, I mean you cant use 100 itunes cards and 50 amazon cards a day, you have to be able to replenesh your bitcoin sooner or later. Is this a trade secret or am I just not able to figure it out
They are willing to take on the risk of a gift card being carded because they know they are able to cash it out using a certain route that not a lot of people know about. The rates that these high volume players pay for gift card transactions are so low anyways that it makes it very profitable for them if they do this on a large scale.
That's why they have volume. They aren't just hoarding the gift cards for themselves, they are cashing it out as soon as they receive it.
I personally would stay clear of being an "advertiser" on paxful for these gift card transactions though. You could get into a lot of trouble in terms of receiving carded/stolen GCs in transactions, that risk is just not worth it for the measly few bucks you may save if you are just starting to trade.