All wonder actors look as if they're made out of stone. In game they cost 1000 of each resource. This patch removes the food cost and increases the stone cost by 50%, reducing the resource total to 3500. Wonders are very much larger than fortresses, therefore it makes sense they cost more stone (still a lot less than the 5000 present in a stone quarry), and food is a resource for units (and technologies); like other structures, it indirectly costs food, because builders cost food to train, and can't work farms when building the structures or quarrying stone.
The only other structure that costs food is `kush_pyramid_small.xml`, which is changed to 300 stone, 150 metal. Furthermore, the metal cost of `kush_pyramid_large.xml` is halved, so it now costs 400 stone, 200 metal, and because the small pyramid already has the economic aura, it's removed from the large pyramid, to further differentiate the two.