Tobago is an island to travel - going entirely for beach holidays means wasting all the benefits of the place. So go for boats, rain forrest walks and to the rivers. Most of the people doing so are used to suitable preparations and wear good walking shoes with socks. But: nobody needs them, nobody walks tracks longer than a few kilometers. Once one visibly does, probably a car will stop and pick you up. On Tobago it's said to be a safe thing to do.
The point with the shoes is a different one. Remember Tobago is a green island with rainforrest. There is rain, rivers and the shore line one comes across sooner or later. So one always can watch people carefully changing their shoes and socks, saving from getting wet, getting the feet dry... I was pretty happy to have learned from professionals before. I had water resistant sandals and walked right ahead, wheather it was through mud, coral rubble or rivers. People admired me for that cheap gear...