I see what you're saying although I'm not sure weddings and graduations are entirely relevant as comparisons. I've been to weddings that were hugely solemn events, so solemn you'd be forgiven for thinking it wasn't supposed to be a happy occasion. I've also been to weddings held in a more contemporary venue with vows that seemed (to me at least) to be so watered down as to be almost meaningless.
There's obviously a point to be made there, but I think we need also to admit that many people, including those who are inclined to be casually dressed and informal almost all the time, act a bit differently when it comes to these kinds of special occasions. THEN the girl wants a white and flowing wedding gown like the one in her dreams. Even people who never go to church want an officiant who's an ordained minister and not just a magistrate in city hall, etc.
And when it comes to graduations, we all think caps and gowns, and so on, are what should exist just as with previous people's graduations. That is true of people who would dress up for almost nothing. How many people would be equally satisfied just to have the school mail out the diplomas and have no ceremonies at all, no walking across the stage, etc.? There is a truth about human nature here, even if not every last person fits the pattern.
Is it the same as the days of the early church?
In structure, in format, it is very similar. The liturgy has evolved over the years, but the basics go back to the early Church.
