The first one taught me a bit about the company and team, and gave me a good impression of the interviewer (the hiring manager), which then led to me doing a work sample. (Without the phone screen I don't know if I would have sunk several hours into the work sample.) I ended up getting an offer but not taking it.
The second one also gave me a good impression of the company, team, and interviewer (a senior engineer) and led to me doing an full day of interviews. Which led to me accepting an offer. The one used Collabedit in addition to the phone.
I know they're not perfect, but it's much cheaper to talk on the phone for an hour than to fly someone in for face-to-face interviews. Given way more resumes than resources for in-person interviews, I'd rather narrow the field using phone screens than narrow the field based solely on what's in the resumes.
I saw the part in your article about work samples, and I agree that they're great, but they are significant work for the candidate. So I think it makes sense to do have some kind of phone call first, to see if there's enough mutual interest to make it worth the candidate's time.