In the UK there is a polite expression that is used to remind people not to hoard space in public spaces: they say "Budge up!" We Americans don't really have an analogous phrase. ("Could you please scoot over?" doesn't really have the same humorous scolding quality to it.)
I've always thought that's a bit telling, actually. We joke about "manspreading", but it's more than that, and I would actually put money on the likelihood that there is almost always some jockeying for position if you just wave 2 groups of Americans toward any kind of gondola without telling them which one is supposed to board first.
I think that the new signs about delays are a good start, but I think that they would be better if they also said something like, "Delays of up to XX minutes at a time should be considered normal."
So, will we now get folks bringing more pocketknives into the parks, with the reasoning that "I might need it to open the emergency kit"?