Excellent write up! This answered some of my questions that I wasn't really comfortable asking creators. A very (and I mean very) long time ago when people were complaining about the price of software I wrote up a Usenet post on why software costs what it does and enlightened a number of people to the fact that yeah, there are many things you don't think about when you're just looking at the list price.
Presumably the contract doesn't allow you to sell product directly if you wanted too. The other thing I'm curious about is that CrowdSupply does continue to list "buying options" long after the creator has gone away. Which makes me wonder if they have some sort of rights to tooling etc post campaign?
Post campaign mouser will continue to order from the creator to keep their stock levels up (assuming the product is selling!). So although the creator may not be actively promoting the product, they may still be doing production runs.
I need to check the exact wording in my contract - but post campaign you can sell through other channels if you want to (which would allow you to do it directly).