It's a touchy one in this case. If I'm reading it right, it doesn't ban wearing a cross, it bans "displaying" it. So they could still wear one under their shirt, etc. Kind of like tattoos ... some places won't let you work there if you have tattoos, but only if they're visible. Or for "covered" piercings, like belly-buttons. It's similar to the saying "Religions are like (man parts), everybody has one, but it's improper to flaunt it".
(edit to add: The big thing here is that government shouldn't be sticking it's nose into private companies for religious reasons where they should have no jurisdiction. There was a case in europe where somebody refused to wear the school uniform, and wore their religious garb. The school kicked them out, so they went to the government. The government said it's a private school, if you want to play, you play by their rules, deal with it or find another school.)
But it's also got to be standard across the board. No cross? Then no burkhas. No cross? Then no pentagrams. No cross? Then no Star of David. We've bent over backwards in the US to make everybody else so comfortable in their religions and beliefs that we've trampled the religions and beliefs of most of the people who built this country. We're no longer invaded by people at sword point (or gun point), but by people using our own laws against us as weapons.
Back when this country was built by immigrants, those people came here, they assimilated, and they earned their unalienable rights. Now people come here, don't care about the language or US culture, don't care about anything other than getting free money and services. There's exceptions to that, but in general, that's how the trend has gone. And it raises tensions, divides us, and is completely counter-productive. Don't get me started on media twisting the public opinion with select "facts" and selectively ignored information.
If things persist like this, both economically and culturally, I foresee another civil war coming; maybe not this year, maybe not this decade, but looming overhead like a tornado waiting to touch down to the ground.