Q: "A group of people are walking on a sidewalk." Does this mean that "People are inside"?
A: no

Q: "A car being prepared for a photo shoot." Does this mean that "A car is being abandoned as all people in its vicinity flee from it."?
A: no

Q: "Sail boarder in midair, while being towed behind a boat." Does this mean that "A person uses his new sail board for the first time."?
A: it is not possible to tell

Q: "Spectators are watching a man who is dressed in a red racing outfit holding a green bicycle." Does this mean that "people are watching"?
A:
yes