Look how this idiot is holding that can of mace way out in front of himself. He is offering it for a trained combatant to take it away.
Facing fash with that same can, I would keep the can close to my body. I can thus block with the other arm if someone goes after the can.
When I am filming enemies I expect to be physically violent, I use the same tactic, sometimes extending the other arm to block an attack on the camera itself.