Yes. They are called analogues and these laws were created ostensibly in response to the trend of "designer drugs" being developed to evade their scheduling as illegal drugs, by staying ahead of the schedules.
There was a crackdown in smoke-shops in New York on the weed-not-weed "synthetic marijuana" and "functional analogues" of cannabis. For a while you could go into any hookah lounge or corner smoke shop, see a case on the counter with 1g and 2g silver-colored ziplock bags, or 5-10g jars... ask for some "incense" or read whatever it says on the bag out loud (and don't say "spice" because K2/spice had already been scheduled).
You'd receive a bag of something that looks like weed, with labels clearly indicating it was not to be marked or marketed for human consumption, that it was a novelty item and definitely not safe, but if you tried it and you actually knew what marijuana was but for some reason couldn't get any real bud, you'd probably agree it was a passable substitute.
Then these shops all started getting visits from the state police, and you couldn't buy them anymore. Their whole inventory would be seized, under the new (at the time) Federal Analog Act.
I hear you can still get salvia and kratom, but I also heard those are both really not anything like cannabis, other than both being organic and having pharmaceutical applications, that you really couldn't easily use either of those and be at all confused about whether it was pot or not.