This is a question with an answer that may vary from state to state. Here in Houston, Texas it is not much of a mystery. It first happened in the mid ‘80s. It happened again midway through the first decade of this century for a similar reason—money.
Seasoned mechanics, and anyone that has been in this business as long as I have, can remember how bad the economy got in the mid-’80s. Construction almost came to a halt in most parts of the country. Our local union folded, and many other unions in Texas failed as well. Nobody had work, so union dues could not be paid to support the cost of operating the local. Perhaps this was collateral damage that trickled down, as it always does.