Two of the main resources people have are time and money. The world offers many opportunities to trade one for the other, at widely varying rates.
I've often heard people recommend trading money for time in the abstract, but this advice is rarely accompanied by specific recommendations on how to do so.
How do you use money to buy time or otherwise make your life better/easier?
See also the flip-side of this post, "what are you surprised people pay for instead of doing themselves?"
You generally pay movers when they're done, so the only risk is the status quo (they don't show up and you have to do it yourself).
This was about paying people at the price level that requires hiring a random person, not hiring professional movers. I'm pretty sure the $20 guy off of Craigslist isn't insured when he breaks your vases, and there's also a chance that if the move goes bad he'll just disappear (no fixed business address). I'm also pretty sure that there's nothing in practice keeping him from saying "okay, now that it's all on our truck we won't unload unless you pay us $300", at which point you either pay, or sue him while they have physical custody of all your property.