When I look at other dried herbs on amazon, they're much cheaper. E.g. thyme is about $10 for 12 ounces, oregano is $13 for 5 ounces.
Weed obviously has higher taxes, more regulation and I presume a smaller market (most people consume culinary herbs as part of their diet, not everybody consumes weed). But I'd expect the price to come down once the regulations disappear.
On the contrary, I know plenty of people who consume large amounts of concentrates and don't use much herbs and seasonings with their food. I suppose unless we're counting third party foods, in which case you might be right.
Prohibition might disappear, but I doubt when marijuana is treated as a legal psychoactive drug it will be unregulated, or even merely regulated the way culinary herbs are.
Second off, much work goes into developing and stabilising a strain.
Thirdly, high quality MJ is grown indoors, with artificial lighting.
Fourthly, it requires a curing process.
Generally, all herbs require curing [e.g., fan-driven air drying at a specific temperature] if not sold fresh; in addition, the work of developing a cultivar or strain is similar for a great many trade herbs that are farmed as opposed to gathered in the wild [e.g., the numerous types of basil, F1 hybrids of parsley, valerian cultivars of varying potency, etc etc]
FWIW saffron is the dried stigma of the saffron crocus crocus sativa so only a small part of the flower