Something was bugging me about the table of numbers, and your post prompted me to do a little research. Check this out:
Number of LDS-hosted scouting units 37,856.
Number of LDS churches in the USA 11,841
Number of UMC-hosted scouting units 10,868
Number of UMC churches in the USA 34,000
Number of Catholic-hosted scouting units 8,397
Number of Catholic parishes in the USA 17,644
(I didn't cover the last three because the labels were too vague, i.e. "Baptist" not SBC, "Presbyterian" not OPC, etc).
Notice the ratio of support. Statistically speaking, every LDS ward in the country sponsors an average of three and and half BSA troops each, while less than half of all Catholic and Protestant local churches sponsor even one BSA troop. Culturally speaking, Mormons can be seen putting all of their support and trust in a non-Mormon, non-religious organization to define "good character" behaviors and values for their children. Catholics and some Protestant denominations, on the other hand, sponsor explicitly religious "good character" alternatives (such as Awana, the Royal Ambassadors, etc), which would explain why their support of the BSA is comparatively lacking.
At the same time most Methodist churches are on their last legs financially, so only active churches with members have a UM Mens organization available to sponsor a Scout unit.