But it's informal...

If ritual is interpreted in terms of practice, it becomes clear that formality, fixity, and repetition are not intrinsic qualities of ritual so much as they are a frequent, but not universal strategy for producing ritualized acts. That is to say, formalizing a gathering, following a fixed agenda and repeating that activity at periodic intervals, and so on, reveal potential strategies of ritualization because these ways of acting are the means by which one group of activities is set off as distinct and privileged vis-a-vis other activities. Yet in a different situation, informality might be stressed to dominate other ways of acting. For example, the formal activities of gathering for a Catholic mass distinguish this 'meal' from daily eating activities, but the informality of a mass celebrated in a private home with a folk guitar and kitchen utensils is meant to set up another contrast (the spontaneous authentic celebration versus the formal and inauthentic mass) which the informal service expects to dominate. It is only necessary that the cultural context include some consensus concerning the opposition and relative values of personal sincerity and intimate participation vis-a-vis routinized and impersonal participation.— Ritual Theory, Ritual Practice, page 92

<idle musing>
An excellent insight! An informal gathering can be just as much a ritual as a formal one—and to think otherwise is just deceiving ourselves...which we seem to be only too good at!
</idle musing>