"would we pay for this?".... and as a cash strapped startup we said no.
The important thing is to see from your customer's point of view. Dog-fooding is just one technique that helps that. There's also: listen to them (and facilitate that); imagine a day-in-the-life; work in their industry; visit them; watch them using your product.
But remember that the rare and beautiful insight is of a problem they didn't know they had.