You can be a petrolhead -- among other like-minded petrolheads, in designated areas where you don't bother other people who simply have no choice whether or not they are subjected to your "taste". It's similar to smokers being inconsiderate and blowing smoke onto non-smoking persons. If I'm a "metalhead", that doesn't give me the right to blast music at 1 in the morning in my apartment, or during my morning commute.