If you own a business you will have to sign a lot of contracts. There are many different types of business contracts and commercial lawyers are needed to ensure you are not signing something that will adversely affect your business or your ability to run it. People agree to contracts in all their daily buying without even realising it. Such contracts are not signed, but include a clause that by doing business with the company you agree to the terms of the contract.
This can be as simple as setting up a bank account or buying a book online. It is in place when you purchase groceries or go to the doctor or dentist. Most people don’t even read these contracts and it doesn’t really matter most of the time. It simply protects the business in some way.