I was able to pick up wooden crates through vanilla naturally occurring walls on nasdara at 5026.50 / 7139.50. I was walking along the walls of a base and the prompt to pick it up popped up. I was able to pick up all of them. I was also able to lower their flag. I notified server admins and they were able to loot through my walls as well (5606.75 / 7182.25), so this is likely happening all over the map.

Walk along the walls of a base with crates against the walls, or items in the building inventory for construction. I was also able to lower the players flag.

Able to pick up crates and lower flags through walls