That's just the point...modern cars are built with a hardened-steel rollcage that can support several times the weight of the vehicle. It's not even something the consumer has a choice in buying...it's just a factory feature. Heck, even the ubiquitous and mainstream VW Passat has a rollcage:
Items like airbags, rollcages, and strong seatbelts in cars & trucks make sense all of the time. Some features originally created for the automotive market (e.g. radial tires) make a great transition to motorcycles for improved comfort, speed, safety, and reliability. Your SV650 rides on radial tires and I'm sure you wouldn't trade them for older bias-ply rubber for sake of tradition. Or would you?
~ Blue Jays ~