You can Hold items that exceed your weight-limit in your inventory by storing items that you already have in your inventory in a container you already have in your inventory. You might consider this a feature but it is exploitable with the way throwing damage works (basically you can one-shot every enemy that isn't immune to throwing damage).
I can however see that this "bug" makes inventory-sorting easier. If you just couldn't throw items that exceed your weight limit this issue would be solved aswell.
