There are so many beautiful places to see in Goa that a vehicle of your own becomes necessary. Taxis are expensive and buses are few and far between. The ideal way to travel is on hired scooters. For five dollars you can hire a scooter for 24 hours. That is the reason you see people zipping past you especially on weekends on scooters. Walking is a hazardous v enture because there are no earmarked footpaths and cars , buses and scooters just brush past you at full speed.
Helmets are unheard of. In my hometown of Chandigarh that invites an instant challaan (ticket) for traffic rules violation. I did not see a single person wearing a helmet.