How is Matt so tall here?

Possible reasonings:

And the most likely…

There are so many ways to use a bench! 

Crowley’s distinctive walk

Lauren Laverne Interview - January 2020

Lauren Laverne:  What are the challenges of playing a demon?

David Tennant: The tightness of the trousers.  It turns out demons wear very tight trousers, which at least gives you a walk.  

LL: A strut?  

DT:  I suppose it is a bit of a strut. A bit of a swagger, yeah.  But it’s just the only way I could get around. There was no great character choice.

LL: Was there any talc involved?

DT:  There was. There is a leather pair…  in one of the time periods I’m wearing leather trousers.  That took… that took some staff.  Most of the time I’d manage to struggle in and out myself, but I don’t know how Keith Richards manages it.

DragonCon - August 2019

Question: Crowley has a very distinctive walk. Everyone has theories on why. What’s your opinion?

David Tennant:  Because his pants were very tight, and that’s what happens…  It was nothing more philosophical than that.  I think demons do swagger though, don’t you?  I imagine demons swagger.  He’s got nothing to prove.  He’s been on Earth longer than any of us.  He can take his time, he can fill his space.  There was also a whole thing, you know, he’s a snake.  He starts as a snake, he comes from a snake.  He’s got snake-hips [laughs] …and tight pants  …and snake boots.  All of those things seem to combine to give him something of a swagger.  Nothing to do with me, it just happens.

Stoic area man communicates using mostly grunts and curses - complete compilation (spoilers!)