This is going to be a grossly generalized list about what a tourist is. Having been one I can say it's mostly true.
1. White almost pale skin.
2. Packs and packs of cigarettes.
3. Camera strapped to their fronts.
4. Bathing suits in leu of regular undergarments.
5. "Comfortable" foot ware.
6. Sunglasses, always.
7. Piles of money that feels like Monopoly money it's so foreign.
8. From a distance you'd think they were alcoholics.
9. They don't know much about their environment.
10. They think they know everything about their environment.
It's how we act on vacation. I do it to. "I'm on vacation!" We read the Wikipedia page before we travel internationally and decide that makes us an expert. We walk around in a vacation haze that is so relaxing I don't know why I don't just live there.
Disclaimer: I love tourists. I love being a tourist. I just think they are amusing in their predictable attire and actions.