I don't really care about pros doing it, but I have a feeling that if the pros start doing it openly, then kids will be trying to emulate the pros, and take steriods in order to get better to be like their idols. Like it or not, professional athletes are role models.
Nonetheless, I don't think that people should be arrested for doping or using steriods. it is not a criminal offense, and if the drug (HGH, for example) was being perscribed legally by a real doctor, there is nothing legally wrong...but they should be suspended and punished by rules from the individual leagues.