The Cold Steel Kraton and Fallkniven Thermorun handles are the result of their respective order requirements. Hattori himself does not use synthetic handles on 99.9% ofl of his own branded knives, and uses various woods, micarta and stacked leather. These are all traditional well established handle/scale materials and in general are considered "nicer" than synthetics by many, including myself. I personally have examples of all types, and my US made CS SRK's handle is fine, having bought the knife in 1989/90.
There have been threads here on BF about synthetic handles and it all comes down to personal taste. Synthetic handles started appearing in the 1980s when new materials such as Kevlar and Valox started replacing the old steel, canvas and leather of military gear. Knives that have synthetic handles have passed military requirements around the world and have been in wide use for the last 30 years. So no, they certainly aren't "garbage".