As the price of fuel rises the price of everything else rises. Often bees are not kept on the same property as the honey producer, they are trucked out to farms on Semi trucks and left then people go out to harvest the honey or move the boxes on to the next crop. Another reason could be due to colony collapse disorder, thousands of bee populations were killed off over the last couple of years and they don't know why. So the supply has gone down with the bee die offs and demand has stayed the same or gone up.
Fuel prices might be a reason for the price increases but I believe also that our bee population is dwindling and scientists are perplexed as to why the bee population are decreasing dice the bees play an important role in world survival since bees pollenate food sources that we eat