Probably because people find it easier to empathise with those closer to them than those further away. It's tied to the idea of Dunbar's Number, the concept tha

Probably because people find it easier to empathise with those closer to them than those further away. It's tied to the idea of Dunbar's Number, the concept that people can only maintain relationships with about 150 people closest to them, and find it harder to care about those outside of said number than those in it. It's not really selfishness or a want for inequality as much as it is a psychological issue that's difficult to overcome. People are simply not 'built' to be able to empathise with 7 billion people at once.