So you have invested 2+ hours writing a cv and a cover letter, and another 4 to 5 getting ready for, going to and finally attending one or more interviews, and you balk at investing another 4 hours on a project, where your abilities can really shine over the competition?
I don't think the argument was about the misc. time it takes to do things. It takes time to commute, it takes time to shower, it even takes time to eat.
The issue is that you're working for a prospective company while not being compensated for it.