The first time I got a clip in a actual video happened all at the same time. I had one trick in Volcom's Let's Live, one in Nike's Nothing But The Truth, and one in the Listen video. I had no idea how to get paid, and went out and bought a physical booklet of invoices and sent them out. Out of all the 3 companies, I only got a check from Listen, which is ironic since they were the smallest company.
As chatbot said, I also later got hit up to sell slams to one of those TV shows that show bloopers or whatever. I got $900 for 3 clips and that's the most I've ever got paid for a single clip. I randomly saw one of the slam clips playing on a TV at a bar, which was pretty funny.
The couple times I filmed stuff for Deluxe projects, they were always quick about paying, which doesn't surprise me since Jim seems like he'd make it a priority people got paid.
Out of all the times I got paid from skating over the course of my life, there's no way it covered the cost of cameras and tapes I purchased over that same time period.
I can't imagine trying to make it in filming these days.