Ah! A member of the sports car set.

Well then let us compare mass. For you picky types divide by 32.174049 to get slugs. If you are from a metric country just humor (or humour) us.

2017 Mercedes Benz SLC Roadster 3,541 pounds
2017 Chevrolet Silverado Truck 4,979 pounds
2017 Lexus RX 450h AWD SUV 4,740 pounds
2017 Jeep Wrangler 4x4 3,941 pounds
2017 Toyota Highlander Hybrid AWD 4,398 pounds
2017 Honda Odyssey Mini-Van 4,470 pounds
2017 Hyundai Accent SE Hatchback 2,553 pounds
2017 Subaru Crosstrek AWD Crossover 3,109 pounds
2017 Lincoln Continental AWD Sedan 4,396 pounds
2017 Toyota Tacoma Pickup Double Cab 4,230 pounds

So on average we are talking ±3,000 pounds. Here is a discussion from of all places ebay. The comment in square brackets is mine.

"When looking for your first road bike, try to be realistic. On average, a $600 to $900 bike will not weigh 15 pounds [This is the legal minimum for a road race]. It may weigh 19 to 23 pounds, but it will still be quite fast (certainly faster than your mountain bike), offer good handling, and be decked out with Shimano or Campagnolo components that will last years with proper care and maintenance. What is the difference between a $700 bike and a $3,000 bike? They may look the same, but there are many differences. On a high-end bike, expect to get components that are even lighter, stronger and more beautiful. The superior quality of the machining and finish of higher-end components make them worry-free. They work like a dream, and even require less effort to operate. There may be smatterings of carbon, titanium, magnesium or other exotic materials that enhance performance and extend the life of the components.

The bike frame will be lighter, and will probably have a more performance-oriented geometry. It will certainly have a more sophisticated construction. Features like triple butting on steel and aluminum frames, the combining of materials (such as a frame consisting of a high-grade aluminum main triangle bonded to a carbon rear triangle, with a carbon fork), sophisticated carbon lay-ups or monocoque (one-piece) carbon construction, versatile scandium alloys, or nearly-indestructible titanium tubes may be found on a high-end bike.

If you're not racing, do you need such a bike? Of course not. All things being equal, will you enjoy owning and riding a $3,000 bike more than a $700 bike? Absolutely. Assuming you can afford it, wouldn't you rather be driving a Porsche than a Kia? Both cars will probably get you down the road, at least for a while. One will be far more enjoyable to drive. Whether we're talking about bikes or cars, performance considerations are important, but so are the intangible emotional elements that reflect pride of ownership, tradition and quality. We've never heard anyone complain that their bike is too good.

In relation to these factors, the weight of the bike alone should be less of a consideration. The overall “feel” of a certain bike may make it better for you than a model that is lighter in weight.

The best way to lose weight on a bike is to get out there and ride it. Soon, you'll be putting less weight on your bike, and that's what really matters!"

So we are talking less than 23 pounds for a $700 bike. Of course if you want the sports model...

Now let's do the math. 23 ÷ 3,000 = 0.77% of the mass of the average car. Now unless this is diamond encrusted it is surely providing less stress on both the pocketbook and the earth while improving the health. Assuming of course that one is not run over by an irate overweight operator of one-and-a-half tons of steel. :)