I agree lead is bad for our engines and if there was an alternative for the same price, (or less in the case of Mogas) available at most airfields I would use it. I would even use it if it was worse for the environment. The environment concerns me not at all in this context.
I’d spring for the Mogas STC (quite expensive for my plane as airframe modifications are required) in a heartbeat if 100LL was not available but Mogas was.
Again, I don’t give a rat’s arse about the trivial lead emissions. I want it OUT of my plane. If it winds up in the atmosphere in insignificant amounts I don’t care.