Using a forklift, barrels, and crates can be removed or loaded onto a vehicle. On the forklift, the crates must be placed on a pallet, and the pallet can be placed on the ground.

This is waaaay more immersion than I want to get into. For starters, the fact you are required to place the crate/barrel on the ground with a pallet means that I'd have to code pallet systems. Not to mention most users would just wrench all the crates/barrels and get them off that way rather than using a forklift. This is a realistic feature for sure, but it's not really fit for Minecraft as a whole.