Ivana,
I bike on average more than 10k. I bike _because_ of the bike paths.
Re Philadelphia - I am not exaggerating, my brother would drive his car and would never stop at a STOP sign ... only slow down; he was typical of the drivers I saw in Philly. The individual who would stop was the exception. Of course, here in the Netherlands, I can count on one hand the number of STOP signs I have seen in the entire country.
Don't be so hard on your fellow countrymen ... they might bike because they like to. I know some Dutch who never bike, they only use their car. I would guess that most Dutch don't think about biking ... the paths exist, parking is a hassle, it makes sense to bike, doesn't it?
The bottom line for me ... I bike here _because_ the paths exist. I lived in the US for 44 years before I moved here and the thought of biking in the US, after I became an adult, never occurred to me; it was only after I moved to a country that was so bike friendly that I decided to take up biking. I got a kick out biking when I moved here eight years ago, and that same kick remains with me today.
I only use my car when absolutely necessary ... it's the bike for me and will remain so.