Things that are so obvious and ingrained that no one even thinks about them.

Here’s a few:

All US americans can go to Mexico EASILY. You’re supposed to have a passport but you don’t even need one (for car/foot crossing). Versus, it’s really hard for Mexicans, who aren’t wealthy, to secure a VISA to enter the US. I’m sure there are corollaries in other geo-regions.

Another one is wealthy countries having access to vaccines far ahead of “poor” countries.

In US, we might pay lip service to equal child-hood education but most of the funding pulls from local taxes so some kids might receive ~$10000 in spending while another receives $2000. I’m not looking it up at the moment, but I’m SURE there are strong racial stratas.