Out here the big shows have an official photographer (OP) as well as private client photographers (PP), all of whom pay a vendor fee to the show.
The PP have to have a client list to the show before it starts. The PP do ring shots plus candids plus videos. Here’s the IG of one such person - https://instagram.com/lindseylongequine?igshid=YmMyMTA2M2Y=
Some of the shows charge a $125 media fee that often enables you to download lo res images at no additional cost. Sometimes that fee is supposed to include video, but downloads generally cost extra.
As a decent photographer with a good camera I’ve almost stopped trying to photograph at shows, even candids, and mostly all I ever did was friends. Sometimes I shoot others for practice, but those get evaluated and deleted. Some of the OP are gracious about seeing others taking photos. It seems to help if you’re dressed to ride. Technically, if it’s a public space and you’re not making money, you’re allowed to photograph.