You know, my favorite examples of modern polygamists in the LDS church used to be apostles, like Oaks and Neilson, who remarried after their spouse died and are now sealed to two women.
But, on further consideration, how about the guy in my ward who was married in the temple, divorced civilly, then married again in the temple to another woman. In the eyes of the state, he is married to only one woman, but in the eyes of the church, he is married to two.
When I was on the high council our SP did a 45 minute explanation of why a woman (in a case just like the above) would not be granted a cancellation of sealing (temple divorce). It is because she would lose the blessings of the sealing and her children would then be sealed to another (and on and on for 45 minutes). This had come directly from a SP training with BK Packer.
If the media ever got hold of that story and was able to tell it in a way that would be understood by the general public and then get it to the NY Times or Washington Post, heads would explode.
The world may wonder at time what happens in the temples, but I doubt outside the church, anyone cares who is sealed to whom. Really why would they care about a fake ceremony with no meaning outside of a made up religion?
I've encountered "Manti Mormon" types here in Hawaii (my daughter in law's daddy for one) who serially marry and divorce just so they can fulfill the 19th century Mo "commandment" to have three wives, so they can qualify for the CK.
Well, the Jews cared who was baptized in a ceremony in the temple. I don't think it is a stretch to think peoplewant to know what they do in those temples.