Earthworm castings business

This looked like it might be a good thing, but it became a little discouraging yesterday when I checked into it.  Why?  Selling price looks too cheap.

You need lots and lots of this stuff.  The trouble is: there won't be time to make enough of it in order to make it worthwhile.

Let's do some quick math here.  I think that the 10 gallon container in the video has enough worms to produce maybe a pound per day.  If each pound can be sold for 30 cents, you'd need about 100 of these to produce just 30 bucks worth of castings.  It may take hours to pull off that 100 lbs worth of castings.  Maybe you can do this all day and make maybe 30 bucks, I don't know.

You'd have to find a market for your castings.  You'd have to ship it out.  There's the business end to manage as well as the production end.

Let's say you sold a ten pound bag online for 5 bucks plus s&h.  Would there be a market for it?  Shipping a ten pound bag even by regular mail won't be as cheap as the stuff itself.  Would people pay to receive this online and why?

Here's somebody selling it for 10 bucks for a 4 lb bag.  Now that is more like it.  But what's the market for it?  Can you sell this stuff?  Can you get a reasonable price for it?