Solar was the ethical choice but it didn't really take off till it reached parity with other sources of electricity production.
Electricity cars are the more ethical choice and last few years people are paying more for it but it will only take off when it comes into parity with gasoline cars.
Solar panels and electric cars are a large up front cost for a very long range, abstract benefit. Buying more ethical groceries is a small up-front cost for an immediate warm-fuzzy.
This shouldn't come as a surprise, most people are tragics for sacrificing the long term to boost the short term - witness the ubiquity of credit card debt.
I'd guess vat-grown beef would fall more into the free-range egg scenario than the solar-panel scenario (although probably with less emotional baggage since beef cattle are generally pictured as happy cows eating grass in a field, whereas cage hens are pitiful to behold.)
