Credit scores

A few years ago I went to purchase something at Sears. The clerk said I would get 15% off if I signed up for their credit card. I was rejected . . . the reason no recent credit activity. I own two properties free and clear, make payments on nothing. Have a nice collection of vintage cars and a nice shop to keep them in. Paid off my mortgage 20 years ago. Have a nice income from Social Security and retirement. Went to my bank to ask how I could improve my Credit Score. They said I could buy some CD's and borrow against them. In effect pay them to improve my Credit Score. Then I thought, with my cash reserve, I could buy anything I need and most things that I want. Last year I bought my house with a 20x40x12 garage shop for cash. The Credit Score system is a racket.