Not only are such classes voluntary, one must actively seek them... there is so little (if any) advertisement, one might think LAB classes are a CIA secret.
Here in Seattle, Traffic Skills is broken down into component modules and taught under other names by the Cascade Bike Club. I think they do a pretty good job with it.
That said, I'd be curious where/how you would suggest that Traffic Skills classes should be marketed.
Full disclosure: I just finally got around to becoming LCI.