[Byte1]

If you do not turn violators in, you may lose your membership and little red book.
Some folks are very sensitive about their impending judgement, since they are very very close to that day. Reminding them of their eternal plight is not being a good neighbor. Since the cross "represents" the gift of salvation to anyone that simply reaches out and accepts it, some find it frightening. Being a good neighbor, a Christian should not flaunt their happiness when some of their neighbors may be facing eternal damnation.
But, rules are rules (not law). Glad I live in a neighborhood that does not have such a rule. My neighbors have beautifully personalized lawns, with birds, gnomes, animal ornaments-- AND crosses. Almost everyone in my neighborhood have crosses in their yard. It gives me a warm feeling when I drive through. And apparently it has not damaged their property value, because when they go up for sale they sell within a few days. $400K-$500K homes sell within days of listing.
This is just my opinion and I can understand how some folks might be paranoid about "certain" rules. No one's personalized yard offends me. I am not going to allow trivial things like a little cross or a bird ornament make me sour in my last 20 years(?). I am going to enjoy the company of my neighbors, rather than alienate them. I don't even care what political affiliation they support or if they fly a flag supporting that party. To some, the "cross" in the yard is comforting and a reminder of what they can look forward to.
Yes, it may violate some deed restrictions. I know that no one that criticizes has ever coasted thru a stop sign or violated the speed limit, which are laws, not just rules. Sorry, if I do not find these little crosses to be offensive. Could it be that there is a gap in some folks knowledge/education that they do not comprehend what the cross represents? Then again, rules are rules and MUST NOT be violated. Did I hear a "Sieg Heil, Comrad?" Just kidding.

Don't take this seriously. Enjoy your neighbors and their personalities. Your neighbor will likely be there when your family is not.