Near my home is a Highway Memorial to FIVE teens who were killed in a tragic accident many years ago. Four of the Teens were Christian and One Jewish. The Four Crosses and One Star of David have stood unmolested on that site for over 15 YEARS.
Across the street is the Kabbalah Center, and as far as I know, there have never been any complaints about this memorial just a few feet from their front door.
A true “atheist” would not care if other people displayed their faith.
It is the Anti-Theist that makes a fuss.
Yes — most people of non-Christian faiths will still respect the symbol of the cross used by Christians. Like your Jewish friends who put up a Star of David. They assert what they believe to be a positive thing.
Militant atheists, and self-hating weak or nominal Christians, will attack the cross. I’ve seen too disgustingly many weak Christians, who think it a great offense to get “too religious.” They’ll even display the Christian fish but quail at the cross. But the cross is where the power is. It’s what Jesus did to take our sins away and open the door to giving us new strength.