Tire Size / Price 33x12.5

In the up and coming weeks, I'm going to be moving up from 31's to 33's. I'd like to keep my rims (rubicon, 16") and have been checking out tires.

I live in an urban area, and need to drive 2 hours +/- to do any sort of wheeling, and use the rig for long distance drives every couple months, so Im planning on a set of BFG At's

According to the summit website,

33x12.5x15's are $150 a piece and 295x75x16's are $200 a piece.

I'm trying to figure out why the huge difference in cost for tires that are the same size. The 15" size lists 2225 lbs and the 16" lists 3415 lbs.
What do these numbers mean? Is either tire better than the other for driving or for wheeling?

For the same money, I could get new wheels & tires, or new tires and spacers to fix the backspacing.

I don't work for the industry, but from someone that has just gone through this same situation I think the answer is simply a supply and demand issue or a higher cost due to lower production number. (Is that the same thing said twice?)

The 2 numbers have to do with load rating. The 16 has a higher load rating. That might be the price difference...I've always wondered myself at the difference when a 33" tire on 15s has more rubber than one on 16s...