Why would you put cinder blocks under your pallets?
Well, how long have you got? The short version is, like solarguy2003, I am in a running battle with ground water at my address.
I started out with pallets directly on the ground.
My wood got "dry", but nothing spectacular, and then that same wood picked up a bunch of water every time ambients got above freezing.
Three of the last five years we get 5-7 days around Thanksgiving with daytime highs at like +40dF and then back below freezing overnights. With pallets on the ground, I would have melting snow running downhill into my dry wood, and early in the burning season too. The hard packed snow I have been walking on to get to my woodpile is a layer thicker than the cinder blocks are tall. Off the packed trails, the snow in my yard is midthigh deep, about 30" accumulated.
We hit +40dF yesterday, 12-30-15. Nice to be out there working in shirtsleeves, but as above, wood on pallets... Never seen that in December before.
December anomaly aside, the other annual event is the melt. Long about mid March I'll be seeing consistent day time highs above freezing on into summer. I need to have all the wood up by then; because the packed snow on the driveway either gets my attention, or my wife gets my attention about the puddle of icy cold water under the laundry machines.
I'll be running the stove into early May for sure. What I can do in say early April is kneel next to my wood pile, take a glove off my hand, stick my hand in the gap between the snow and the pallet, and my hand will be literally dripping wet with condensation in a matter of seconds on the south side of the stack. Same day, other hand, north side of the stack, I can see little tiny beads of condensation on the skin of my hand in moments.
When my wood pile is 12%MC and there is that much vapor in the air, the vapor is going to end up in my cordwood. I can lift the wood above the worst of the vapor layer, and this year am adding plastic to the underside of my seasoning stacks.
All of the above ignores direct pumping of water out of the ground into the stacks. A dry, hot stack of wood, at my house, will pump water straight out of the ground into itself. I have about a cord put up, completely wrapped in plastic on all 6 sides for the spring 2016 melt. Hopefully it works,