Bob,
Hmmm ... so I guess you would discount the results of the standard ASTM test used by the National Lubricating Grease Institute - NLGI - to evaluate water resistance of greases?
ASTM D-1264, % loss @ 175F:
Schaeffers synthetic blend grease with moly, NLGI #2 - 5.4% weight loss
"GLC", multipurpose synthetic grease, NLGI #2, a lithium complex grease - 1.6%
"GHD", HD synthetic grease w/ moly, NLGI #2, a lithium complex grease - 1.8%
"GWR", Water Resistant synthetic grease, NGLI #1.5, a lithium complex grease - 0.9%
Just to make you feel better:
Mobil 1, lithium complex synthetic grease - 6.0%
I know of no materials related issues that would prevent the formulation of a water resistant, PAO synthetic grease with a high quality, lithium complex thickener. Now if you are talking about some 99 cent per tube stuff, perhaps you are right. The first two products I listed are $4.00/tube, synthetic greases and "GWR" is $4.70/tube. The Mobil synthetic grease is also $4.00/tube....