The problem is that the credit system was not designed for society, it came out of a business need. In reality, you don't need a good (or any) credit score if you don't need a loan... but if you do need a loan, the person giving a loan wants to know if you're likely to pay them back.
The credit agencies decided they were scummy enough to collect as much personal info as they could, and sell it to those companies so they could asses that risk... When you get a full credit report, its actually data about you and your accounts, the score is just the distilled version of that data to make it "easier".
Finally, credit score is not always the last straw, depending on what kind of business you're working with. Many smaller companies might be willing to work with you regardless of your credit score, however, they might adjust the terms of the deal...