Several:

1. That using your shoe to flush a toilet in a public bathroom is somehow "more sanitary" than using your hands (Chat Icon Chat Icon )

2. That tipping garbagemen and your postal worker is normal (uhm reallyChat Icon Chat Icon )

3. To turn my head and NOT just rely on my rearview mirror if I am driving and about to change lanes (yes there was a thread just on that topic! Chat Icon Chat Icon )

4. Shoes or no shoes inside the house? And that changing your bedsheets less than 1x a month is Chat Icon

5. That its "rude" to open food inside a supermarket or a Walmart/Target while shopping (even if you plan to pay for it when you finish shopping).Chat Icon