I wash dogs faces with white vinegar as de skunking agent. They kind of like it. But the concept seems like a good one. A supersoaker full of ammonia, tabasco, clorox, gasoline or paint thinner would cause permanent and discourage damage on the squirtee. Squirt guns are perhaps higher profile than aerosol cans, but there seems to be some variation in propellant. I believe hairspray is the fuel of choice for the pvc cannon crowd.
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Dance like you have never been hurt, work like no one is watching,love like you don't need the money.