Derek...gang members may want anything that you;re wearing or want what you have in your pockets or what you wear around your neck or the car you drive or even your girlfriend. You can't live life thinking "what if? what if? what if?" otherwise you'd be afraid to leave your house and you wouldn't be a happy person. And by the way, gang members are not the only criminals. They come in all shapes and sizes. Even sweet little graymas can be criminals.
Relax. stop worrying and obsessing over every little "what-ifs?", that's no way to live a life.