They cost money for both parties though so in that sense it's fair.

I agree with the statement "they cost money for both parties" but I disagree with "in that sense it's fair."

Individual consultant: loses 5 hours of interview time (and commute time) or take-home exam. Let's call it $800 for the sake of argument.

Company: loses 5 hours of interview time, plus the time it takes to "quiz" the exam.

Individual loses money that he / she uses to pay their mortgage.

Company loses profit because the time spent interviewing the candidate could have been spent working on feature Y of the application. So shareholders / VC's lose.

So you're saying it's fair that the individual contributor who loses half a day's pay in your interview process is equivalent (you DID use the word "fair" so that's an equivalence argument you made) to a company's loss of a few hours out of the many thousands of man-hours they rely upon? It's a .0001% of their profit, assuming the employers don't work a few hours more to make up for the lost time, because they will (they're salaried!)

Consultants also do not get paid vacation, or paid sick leave. They also don't get any of the benefits that a lot of regular employees get. But that's part of the game, they have to account for all of that which is why they earn much more per hour. A lot of those "customer acquisition" tasks cost time and may not necessarily yield a return, but that's part of the extra risk consultants have to assume and why not everyone is willing to do it.

Maybe all true with regards to cost considerations, but it doesn't support the notion above that a candidate's wasted time and money (vacation time and sick time costs money for an FTE) and a company's wasted time are somehow .. 'equal'.