Buying a house or a car with a mortgage/loan is the main area where it comes into play - and it shouldn't shut you out, you would just end up with a higher interest rate. I'm not sure if your credit can be so bad you wouldn't be able to buy a house or a car on credit (they can always take it away from you). Another area would be if you wanted to take out a loan. Same basic issue there as it's hard to get an unsecured loan - whatever you use as collateral, they'll just take from you if you default on the loan. Not much risk there for the lender.
My preference is to pay for everything in cash and have no electronic records.