So basically you're correct about them being place holders.
We use them because no builder really ever uses ore blocks, sponges etc! So it allows us to make large w/e commands knowing we won't destroy any of the build. Because if you build in say Wood and you have trees and you want to change that wood to something else you have to make a ton of small W/e edits instead of 1 large one. If we have ores we just change it to what ever we want not having to worry about replacing or editing any other part of the build.
It's also really useful for painting as we can just use brushes and paint it on and for the same reason we can paint with ore blocks and replace it once we are done with the build.
In the picture you see here the terrain is already done because I already know what the diamond, Gold and emerald blocks are going to be turned into so I don't have to worry about editing parts of the build that I don't need.
Jan 24, 19 · +2 · Like · Report
Jan 24, 19 · +2 · Like · Report