While you can not bargain at thrift stores, you can do this at garage sales. One of the places to look for advertisements about garage sales is the Lincoln Journal Star, a major local newspaper. You can access its section about garage sales on the internet. It is useful both for your study and other purposes, such as banking. There is an office that deals with social security number.
Many people have a savings account and a checking account.
Once you are in this country, you need to get used to using checks, credit cards as well as cash. Cash is not often used in people's daily life because it is not convenient or safe. Also, since a lot of Chinese students or scholars have some source of income, such as assistantships, which will come on a monthly basis, it is important that they have a bank account so that the money will come to them through the bank. This is the place where you will have the orientations once you arrive here. It is also the place where you change your I-20 form and seek information that concern your status as an international student or scholar.