Also, I think head hunters want text so their software can categorize you and match you with jobs. While LaTeX makes it look pretty, it might not always be feasible to use it.
It doesn't matter all that much whether the employer is looking for somone who uses underpowered tools to produce their documents, or wants you to spend a lot of time preparing a CV but can't be bothered to have a real person spend half a minute looking over it before binning you, or has inflexible work practices that favour absolute conformity over using tools and processes that make each member of staff more effective. They all reflect badly on the employer's hiring process, and by implication on the people you are likely to be working with if you get the job.
Perhaps rollypolly did want to single out one case, or maybe (s)he was just being diplomatic.
This. When I have recruiters calling me based on my very plain CV done in LaTeX, especially when I'm not even looking for work, I don't really feel any urge to respond to an interview request that starts with "please send us your resume in Microsoft Word." Some firms use strict criteria to whittle down their list of applicants; I feel justified in doing the same.