At my school, they don't require gym, but they require you to do an extra-curricular sport. I personally don't do gym because I have a heart problem and I can't run for more than 20 minutes without going into asthma like symptoms. But I still do golf as my extra-curricular sport.
PE is very much required in my school. Not only do you have to take it, but you can actually be held back senior year for failing it. We have a physical fitness course every two weeks(Track, Weightlifting, Jumprope etc.) and in between we learn how to play sports from Archery to Football and Discus to High Jump. We're graded on participation, effort and final outcome(Depending how fit you are according to the Physical Fitness courses you may or may not get some leniancy) So, growing up with PE like that since the 6th grade, it gets stuck in your head that you need to excersise. I do weightlifting twice a week and play baseball, i think it was 83% of students participate in an extra cirricular sport or wieghtlifting, according to our school's survey. In short, yeah I think PE is definately needed.