Still not the best definition...

Would blanket-charging black people more for insurance (car, health, or house) be fair? Actuaries would say it would be. Non-actuaries would say it probably wouldn't be.

If you're doing a movie on Shaka Zulu, do you cast a white woman to play him? It isn't "fair" that some groups are arbitrarily excluded from top-billing of any given movie, after all. Plenty have argued this exact point (though usually the reverse scenario example) as being a matter of fairness.

The Nigerian complaining about example #2 also doesn't let Nicaraguans into his store for the simple reason that he doesn't like their particular skin color. He's fine with Nigerians, of course. On a macro-scale, they're both "black", they're the same race, but he's hating based on skin tone. Most people would call "discrimination based on skin tone" to be "racism", but based on your wording, it is not the case here.