More like Sunglasses,it's that obvious. The fact is these type of disasters are far more prevalent with these molded, plastic housings. Not to mention far messier. Not only that, but many are destroyed upon removal, (much like the photo in this thread shows).
It doesn't matter what happens to a steel canister in order to get it off, because it's going in the can regardless. No matter how you look at these things, they're far more problem prone. Especially when you've got some kid doing it for a few bucks above minimum wage, with the mechanical aptitude of a bullfrog.