"Olive egger"can be used as a marketing term, to get people to buy more chicks & pay more money. Could be an unethical seller (i.e. they Know the resulting offspring will likely lay lighter green eggs), & could be the offspring hatched from dark brown/blue egg cross, & the resulting colors simply werent very olive. I have some olive eggers that lay Very dark olive. Most came from blue egger/welsummer cross, & oddly, blue egger/isa brown cross. Blue egger/cuckoo marans cross are mostly a comparatively very light olive. And some eggs from above crosses i wouldnt consider olive colored at all, just a medium green. Technically all olive eggers are easter eggers anyway. Egg color shades will vary.