Thanks for the ping. I wasn’t aware that LCMS prohibited Masonic membership. I did know that WELS prohibited it, but was never sure why. It never much mattered, since I was never in any danger of joining a Lodge. WELS also doesn’t like Scouting, and that is an issue for me.
Even Missouri has had its reservations about scouting, mainly focused on the nomenclature of "merit" badges because the word carries a lot of midieval baggage about works righteousness and the treasury of the saints, indulgences, etc.
The same goes for a lot of those wishy washy memorial services where you have a Christian pastor, Hindu priest, and a Imam all praying together.