One side of synthetic fuels which I think is so far not discussed is that using them would potentially separate the cost of fuel at the pump from the cost of oil, and from all the other things which use oil and hence compete for price in the oil market. If your cost to manufacture synthetic gasoline which uses wind/solar/small nuclear/etc power is only based on your capital cost to create the manufacturing facility and then the local labor rates, you'll potentially disconnect the price consumers pay at the pump from other global events and markets.
If smaller synthetic fuel manufacturing sites can be built for local markets, the transportation cost for the fuel to reach the pump will also be much lower, again reducing fluctuations in the price. The main driver of gas prices then will just be the consumer demand. This may stabilize gas prices, which is a valuable thing, even if it's at $8/gallon.