I've been a Paper Conservator for 25+ years.  You seldom meet folks who
need to do this, but there are some.  I agree it makes life more
difficult and I would never do it myself.  If you have inexperienced
folks handling unmated works, maybe this is a good idea.  If you are
handling unmounted photographs, maybe this is a good idea.  I never use
gloves myself.  They may have been just trying to make the point that
paper is sensitive to dirt, hand oils and...

Timothy Vitale
Preservation Associates
831-684-2731