Dont feel alone. I also have a Rebel, and it also gets crap MPGs. In comparison, I have a Honda Civic Type R that I can get to return 38-40 mpg on the hwy...in all honesty I have never driven a vehicle that I wasnt able to get, at least, the MPG on the window sticker, but that Rebel will not do more than 15 mpg, and I dont really care because that is not why I bought it.
I look forward to my TRX showing up so I have blower noises and a loud exhaust to comfort me as I pull into the gas station.
Hydro Blue...almost every option (no tech package or beadlocks)...waiting...waiting...waiting