The use of contracts is the common way individuals, especially those engaged in business functions, come together and set forth conditions in which each side agrees on. Its primary purpose is to override the far to easy potential for our mammalian and dominant left brain to resort back to the default of might makes right. This is a large part why the classical liberals Bastiat and Spencer believed it was necessary to have a small republican form of government to limit State power. Given the present conditions of civilization, perhaps contracts are required, yet what actually underlies contracts is what's insightful.
When you're on a road anywhere in the world, you'll see how much people driving cars cooperate together in an inherently anarchic mode of transportation. Of course driving etiquette will vary depending on the cultural context, with different rules establishing what is suppose to be acceptable; like from what I've observed in Japan and even parts of the US, is they take a more orderly and conforming attitude to driving compared to their counterparts in Brazil, Cyprus, or Thailand, which from an outsider's view would seem to be completely chaotic. Yes, there are also certain contracts usually in place governing liability and tedious bureaucratic licensing requirements, but these aren't what's making people from not crashing into one another. There's a more crucial contract, one that is is more lasting, more genuine, and one that's acknowledged by anyone with a slight humanity—respect.
The surf lineup is another sort of activity which is inherently anarchic, out in the ocean you're at the mercy of nature and being with your fellow humans in that type of environment its important all are respecting the spot's vernacular rules. For both driving and surfing, most people choose to respect one another for their own self-interest in order to get somewhere or ride a wave. It's fallacious to think respect as a reciprocal value "doesn't exist" or is something arbitrary like the countless of ethical systems around the world. Sure, humans end up creating rules for social engagement, though something like respect stems from a belief in autonomy and individual volition; the idea of respect is only respected because people want to be respected.