If you're at a public range and not anticipating other people entering and firing different calibers, you're probably pursuing the wrong hobby. I don't constantly monitor the coming and going of other shooters. Yeah, it sometimes catches me unaware. But, I welcome the interruption to further develop my reaction to distractions and increase my focus. You can turn a negative into a positive.
I just hope the bad guys use quite guns that won’t startle anyone and shoot nice and slow