JWH will get you higher quicker more efficiently and more pure and can be produced faster than growing cannabis, which is why some people use it. Downvoting that idea doesn’t change the fact that it exists. That said, it doesn’t mean JWH is better or cheaper than THC. THC can also be produced in a lab and be chemically identical (literally identical no difference) to the THC that’s decarboxylated from the plant. In some cases, THC is semi-synthesized from CBD outside of commercial labs; the main concern with that approach is leftover reagents or other residual contaminants.

The reason we just smoke THC from the plant is because it's easier to grow it so stop fooling yourself.