You are probably right in your assertion regarding alcohol, however I suspect it may be possible that there are other compounds unique to various flavors of liquor which may influence the overall effects in various ways. These compounds may not be perceptably psychoactive on their own.
The same goes for strains of marijuana, beyond THC and CBD other psychoactive compounds are inconsistently present with uncertain psychoactive effects (if any). Further there may be complex nonlinear interactions (e.g. two compounds produce no effect but adding a third can change the experience, particularly if you consider reaction products from combustion).
In any case the uncertainty is good for marketing.
The same goes for strains of marijuana, beyond THC and CBD other psychoactive compounds are inconsistently present with uncertain psychoactive effects (if any). Further there may be complex nonlinear interactions (e.g. two compounds produce no effect but adding a third can change the experience, particularly if you consider reaction products from combustion).
In any case the uncertainty is good for marketing.