I personally know 5 guys (I'm friend with 2 of them) that were arrested for almost 1 month waiting trial in a EU country for trying to steal a national symbol (it was a banner with the flag of that particular country).

They were EU citizens, they were in another EU country and still, they were arrested 1 month, had to pay a fine of around 5000 euros each and to forfeit their right to enter that country, even being a Schengen country, for some years.

I know that this case in N. Korea is much worst, but you must understand that some countries (even free and democratic countries) can take this kind of things very seriously.

I hope the guy get's to return home, but he really showed very poor judgment.