Road trips are the ultimate way to get around. You are in control when you drive. This means that you can stop wherever and whenever you feel like it. Unlike riding a bus you can stop and smell the roses. Driving is more expensive than taking the bus because you have to pay for gas and possibly tolls and parking, but the journey to your destination is a fun experience.
If you do a lot of shopping on vacation, driving is better than flying or taking the bus. You don't have to pay an exorbitant surcharge or worry about security. Driving is especially helpful if you plan on bringing back craft beer that is not available where you live.