It depends on the size and formality of the event, but part of being an adult is understanding that there's an implicit code of conduct (our social rules), and

It depends on the size and formality of the event, but part of being an adult is understanding that there's an implicit code of conduct (our social rules), and observing those by being on this planet for more than 20 years or so. Having to explain to be respectful to an adult is just pandering unless they've already shown themselves to be a disrespectful person.