What cultural faux pas should I try to avoid making in Illinois?

We asked people in Illinois if they could share any humorous cultural blunders they commited. For new expats, keep in mind that these incidents are an inevitable part of expat life. Learning to laugh about them is the key!...

Other Questions:

•  What do I need to know before retiring in Illinois?
•  How do I meet people in Illinois?
•  What is life like in Illinois?
•  Is there a lot of crime in Illinois?
•  Is there a lot of diversity? Are people in Illinois accepting of differences?
•  What are the schools in Illinois like?
•  Is the cost of living in Illinois high?
•  What advice do you have for expats having a baby in Illinois?
•  What are healthcare services like in Illinois?
•  Is the cost of living in Illinois high?
•  What type of recreational facilities are in Illinois?
•  What is the weather like in Illinois?
•  Are there good restaurants in Illinois?
•  Where will I buy groceries and do other shopping in Illinois?
•  What are the visa & residency requirements in Illinois?
•  Are healthcare and health insurance expensive in Illinois?
•  What do I need to know when buying property in Illinois?
•  Are foreigners allowed to own property in Illinois?
•  What appliances are typically included in a rental?