There have been some changes, indeed! Who would have ever guessed the Corps would divest of tanks in order to gain the personnel and financial overhead required to develop and field an anti-ship missile capability?!
When I was in, we only used the liquid Kiwi stuff to blacken bare leather before going over it with traditional shoe polish - it was a good base coat for field boots. Garrison boots still got a spit shine like black leather shoes - especially when I was at a joint USMC-Navy schoolhouse in Pensacola. We went the extra mile to show the Sailors a thing or two.
I was also in when we transitioned to the brown suede construction worker boots. That's another matter entirely!
Semper Fidelis, my brothers!