It doesnt look like anyone here knows that making a demo means taking resources away from the development of the final product. If you read the announcement again you'll see thats exactly the reason they are delaying the demo. Besides, we get the editor too. Which other game demo have you gotten the in-house editor with before?
They dont earn money by releasing a demo, they earn praise and positive feedback. Nice words dont put food on a table. Selling a product does.
Also, dont you want the final product to be all it can be or do you just want to test the demo asap?