Miraa is a drug. Just accept it. It alters your brain function. It's probably why most merus are not "normally" adjusted. Most merus are either drunkard (miraa get you to alcohol and bangi
- and angry like a mkissi - I normally confuse the two - by way they argue or talk with lots of "hasira".
The somali conflict many believe has gone long because miraa has hallucinating effect - and many somalis don't know their country is kaput.
Yes Miraa is lucrative but like Coca or opium farming - it eventually destroy the society.
I have seen it at micro-level in Embu in-laws. Miraa just accept is a drug. Th meru that do well are Imentis - and they don't grow it - they grow coffee,tea, bananas and such horticultural crops. Nyambene and such areas remain backward...with kids abandoning schools, everyone is probably addicted to miraa and alcohol - if not slashing each other.
You were on a right path until you mentioned Meru Nyambene, and since I am more conversant than you I have to correct you where wrong. You see Meru have chewed Miraa for centuries since the days of Meroe c 800 BCE- c350 CE where all horn of africa kabilas probably started chewing. Miraa is more of an institution than commercial product, its somalis who commercialized Miraa. Miraa is not unique to Meru and has Meru ever anywhere been recorded to suffer from its effects. If they were adverse effects even the colonialist would have clearly documented. But what colonialists documented when they arrived in Meru and I quote "This community seems to fare much better than others we have encountered" so clearly No negative Miraa effects.
Just to enlight you Embu, especially mbeere have just begun muguka/miraa farming in 90s they have no tradition of khat nor any history, for embu/mbeere its purely commercial they know nothing else. Thats why they are always at loggerheads with Merus when sharing the Miraa money, from the last disbursement they got 160M with Meru 800M and Tharaka Nithi 40M. They complain it to be split 50/50 but even a std 2 kid in rural bomet knows thats a mirage. In the miraa taskforce out of 10 members they have none. Basically you can't let people who have never struggled or even put a coin in european courts to stop the Miraa ban nor have they even contributed a cent to market Miraa internationally have any say.