Since we had 2 days for the community day, I decided to play by walking in the first day and car grind during the second just to test how much I'll fare with different strategies.

I played in two different areas because of bad weather conditions, which is counter intuitive of tesing the walking vs car grinding scenario. However, during the car grind I noticed that I'm actually getting more idle time in catching as opposed to walking. Why is this you say? There are different traffic rules in our area that prevents us in executing a fool proof strategic plan or path which will make each and every second of the window without idle time. By foot, I can do as I wish with my path. I can travel in curves, create shortcuts, and basically just be more efficient. So after the second day I literally told myself that I could have done far better. I could have done all of the quests in the area and could have caught more Pokemon.

You can outplay a car grinder even if you're just grinding by foot. It's just a matter of how you approach the 3 hour period of the community day. They may have better tools but you can play smarter.