Why you should ask for a bill after every purchase?

This video explains what is a bill and why it is important?
Always make sure to collect a bill in order to safeguard yourself, when buying from a seller. The bills offer to protect of benefits of the buyer and seller.
In absence of a bill or receipt, the buyer loses the right to complain under the law if the goods turn out to be faulty or not up to the mark. Bill also ensures that the shop keeper pays the taxes to the government.