I think you're misunderstanding me though. I'm not saying they shouldn't require that you do a work-from home assignment. I'm talking about the fact that most "auditions" I get are far more than a simple homework assignment, and those employers often expect far more time than I have available. Like I said in another comment, they aren't just asking me to solve a to-do item from their to-do list, they're also asking me to install their codebase (and all that entails), learn it enough to isolate the problem and formulate a fix, and THEN and only then do I actually get to implement my fix and submit it.
That's more like contract work and less like an audition.
To make another comparison and riff on the word "audition", as an actor (I am one), when I go audition for a play, I'm not rehearsing with other actors and performing on stage for 1 night (the equivalent of a 1 week contract in web dev). Instead, I'm showing up with a prepared monologue (60-90 seconds) and possibly doing some cold readings (the equivalent of a "homework assignment"). The entire audition lasts an hour, maybe two.
One of those requires far, far, far more work than the other -- and the second one is what an actual audition is.
So what I'm getting at is that the problem isn't a merit-based approach -- the problem is a merit-based approach that doesn't respect my time and energy.
Does that make sense?