Why does everyone in this movie..

They're...all...Shatnered!

I'm thinking I'll likely go where I'm sent!

To...emphasize...the...urgency...of...the... impending...doom.
"H U R R Y ! R U N !"
Wait, never mind, this is a disaster trope. We actually have all the time we want to stand here and stare at each other for no good reason. That lava/tsunami/ tornado/ crack-in-the-earth won't kill us until we get to say our coolest lines.

Even the volcano paused to let them get a couple of extra speeches and fights in.