Time is money.
I like how the BC I bought came with a 15 lb hopper and hand crank and for a very good price.
All I needed was a 5 gallon Homer Bucket and I was good to go.
I don't have the time or resources to construct hoppers and belt-driven motors/tables.
I used the hand crank a few times in near 100 degree heat and humidity here in FL, but quickly realized that using a corded power drill to run the rollers is a much easier way to do this task.
Plus, when you are grinding harder grains (e.g., crystal or roasted malts), the power drill works harder, not you.