A good question is why do you need to travel with 3 different cameras?
Different cameras for different needs: XSi DSLR, s90 - carry at all times; my third will be replaced with a SuperZoom but none have tickled my fancy yet. Hoping for a bit better high ISO performance and improved electronic viewfinder.
AAs are convenient, but are generally dont last as long as li-ion batteries that are smaller.
Depends on your shooting style.
I've taken some of my best photos in Paris with the old Canon s2 superzoom, which uses four AA batteries. If the batteries ran low, I could have picked up replacements almost anywhere.
Li-ion batteries are very good but may not fit the needs of everyone. I think the OP has a valid point about why he wants AA's.
Inform, yes, but don't try to talk someone out of it.
--
gail ~
http://www.pbase.com/gailb
My Canon s90 BLOG:
http://www.digicamhelp.com/camera-logs/canon-s90/canon-s90-first-impressions/