I've come across this countless amounts of times. And whilst it would be nice to be able to stick just to clients who understand your work, life isn't like that.
If it's a brochure that requires printing externally, then point out that it would need crop and bleed, and that the file definitely needs to be done in InDesign.
However, if it's for a publication that's being emailed around, or printed in-house, I'd suggest PowerPoint.
For the company I work for, I've created a backup template in PowerPoint for the publications that I work on, so, in an emergency (lets say I actually decided to take some annual leave) they can bang-out a very simple, cave-man version
Try politely explaining to them what you actually do. Because what you do isn't just dropping in their text and some nice pictures. It's working on the alignment, formatting, sentence structure, design, over-all page design, and pagination. It's easy for those who don't have the creative skills we do to forget that it's not that easy.