@steevc, Yes, you've raised the correct points for sure and that is because, we cannot take the Random Photos just because they are visible while you search, just think it's just like using your bike because you've left your keys on the Bike.
So, always we have to use the pictures which are clearly mentioned as Free For Use or pictures which you purchased, otherwise as you said it can be an issue, and also we are not producing original content.
Wishing you an great day and stay blessed. 🙂