The guy was a total dumbass.

But what exactly does meth have to do with his actions, other than the fact it fell out of his pocket and had a lot in his backpack?

His actions aren't a direct cause from meth. It's directly from his stupidity.

You shouldn't do meth because it corrodes your mouth, it's addictive, it's makes you paranoid, and it's frankly, a huge waste of money in my opinion, it isn't even that good.

But this man's actions has no correalation with meth. Another scumbag of a criminal.