Why do some jobs send newbies to go get ridiculous items (e.g. bucket of steam, striped paint, headlight fluid)?

I've seen a few explanations bandied about, but I don't really understand the logic. In my understanding, when people lie about things without a clear benefit, it's usually about power dynamics-- in essence, bullying. Certainly, when people lie to me about things, and I find out that they're liars, I'm much less likely to trust them. However, a lot of people seem to think this practice is productive in some way. Where's the disconnect? What am I missing?

EDIT: What's with the downvotes? I thought this was the "no stupid questions" subreddit. I'm not trolling, I'm asking what would, in other contexts, be considered a 'stupid question' on a subreddit specifically for that purpose.