some people flip out some don't. When one of my cats got hit a few years ago the person who hit it was worse off then i was. she was hysterical and we had to call someone else (i think her mom) to come and get her because she was unable to drive home. literally she was just balling like someone just told her he parents died
because pets are more than just animals to people... they're family members. they put them in pictures, they spend lots of money for their vet bills, they feed them, remove their poop, they have pride for their pets (even if they're uglier than hell, they still love them), they include them in those family stick figure window decals that you see on the rear windows of minivans and suvs...
people love their pets very much and get sick when they don't come back and don't know why...
my cat got out one night because she was in heat... she always came back home within a day. after three days, i was sick and really worried. i looked all over the place, clanging her food bowl and calling her name (which usually has her meowing and running with extreme excitement towards me). i heard nothing. i went around and asked every neighbor if they'd seen nibbler (the cat... she's a tuxedo... yes, we named her after the futurama pet), and no one had. after a week, i just figured some animal ate her or something and was very depressed. then, finally, one of the neighbors came and told me about some flyers they saw that said "found: black and white tuxedo cat". i called the number on the flyer and, sure enough, it was nibbler... she was in a house a mile away. apparently, the people were having a dinner party and when few of the guests were at the door and rang the doorbell, the host opened the door and nibbler just walked right in the house as if it was our house (the houses look nothing alike... we had a townhouse and they had a large 4 bedroom house).
the point is that i was scared and sick from the stress of worrying about what happened to her.