For example, I don't think I've ever been to one which does elimination rounds, no matter how many players are there. Swiss ordering wins it.
There's actually a good argument to be made for running Swiss-only, although I do sort of prefer the Swiss-plus-cut format for pacing and tempo reasons.
What is sort of indefensible, to me, is taking a relatively well-ordered set of players and then saying (as the current guidance from FFG's Organized Play apparently does) "eh, screw it, you also have to run three more rounds of single-elimination". The point of those extra rounds isn't to identify a champion, since five rounds of Swiss for 32 or fewer players will have already produced at most one undefeated player. The point also can't be to confirm that the leading Swiss player is the "real" best player, since single-elimination is the worst possible format for doing so.