you don't have to fight to the death though, most perps would be deterred by most victims if they actually fought back or even gave the impression they'll fight back
b) People who realize most umbrellas are hot garbage, and understand that an umbrella that won't break if you even stand on it are probably going to last a while.
In Chicago they sell some pretty heavy duty umbrellas because the wind is very strong. I've since left Chicago and do cherish the umbrella I got there for how heavy duty it is and the fact that even monsoon level winds will not flip it inside out due to the reinforcement in the frame and fabric.
But then I realized I'd rather just give someone my cell phone and wallet instead of a fight to the death with an umbrella..