Exactly. They play chess for a living.

You need to care about the bits around the actual chess playing, but regulations for these things are overwhelmingly made of "play nice, be reasonable, don't be a dick" rules. If you try to play by those high-level rules, apologise if you break the nitty gritty of the low-level rules and fix things at the earliest opportunity, it shouldn't be a big issue. Also, things like dress code can easily be a "not an actual rule, just convention" sort of affair.