This is Indianapolis... the nerve center of Indiana. Therefore, they liked basketball here, and football too! And racing! So, don't insult the Pacers or the Colts... and well, I don't like racing or pro sports either.. so just root for the Purdue Boilermakers like me! :)
Indy IS a bit of a conservative town, but the people are VERY friendly overall. Wherever there's a corwd of drunks, there are always the drunkards looking to cause trouble, but all in all I have never not felt safe in Indianapolis.
Tips - Tips are customary in Indianapolis as well as the whole state. Unlike some foreign countries our waitresses rely on the tips to survive. In Indianapolis the common tip is 10-20%. Sit down hamburger restaurants tend to be around the 10-15% range. However, if you are eating at a nicer restaurant, 20% of the bill should be added on.
I've always found Hoosiers to be friendly, and helpful if you need it. These people tend to be quite serious about their basketball (especially high school and college), so you can always get a conversation started if you talk about basketball!