Worst customer service and practices

I have had to worst customers experience not just ones but on 3 occasions. I honestly don’t know why I ever go back. Bought 2 chairs but it was too high for my kitchen counter. So I went to the exchange it for smaller ones. They then charge you 5% for exchanging anything. I did not return just wanted to exchange but was still charged. Went back home with shorter chairs. One has a scratch on it and is wobbly. Their refuse to exchange it says I signed their form when taking it. The scratch was under the leg plastic. I left the chair there and want a refund. Their practices and the way they do business is not ethical.