the world entire uses about 100,000 tonnes of titanium per year. There doesn't appear to be much data on what the bicycling industry itself uses. Possibly due to the way it is purchased - through parent companies or from fabricators. So all titanium produced across the planet per year by your estimate uses 150,000,000 barrels of oil per year. The world produces about 30,549,000 barrels per day. That would mean that the titanium industry uses aprox. 5 days worth or about 1.36 percent of the total oil consumed on the planet annually. I did not verify your assertion but assuming the production of titanium of all types for all uses that number still seems high. Where did you get your data? Honest question. I guess it really doesn't matter. No one is being a bad steward of our earth by purchasing a titanium bicycle or bicycle parts. No guilt. No shame. Wonderful, abundant, naturally occurring, exceedingly useful product. It was placed here for our direct use - or else it would not be naturally present.