Auto zone Liars Whittier, California

I purchased brakes for my car about 6 years ago from auto zone ,, when my brakes where down to nothing I would take them back in because I had the lifetime warrenty , they would exchange them for free.. Today they tell me no that's not there policy anymore they only return them if its a manufactor defect, and that the corpret office is cracking down on the stores.. Well I think that's such a double standard to change the way they do buesness just to fit there needs.. I mean the object of buying the more costly brakes is for the life time warranty.. I feel like I have been lied to and tooken advantage of for the sole purpose of them getting more money out of me.. They just lost my buessness . I am disgusted with auto zone . It's one thing if I purchesed the brakes knowing that it would only be the manufactor defects but I feel coruresd into spending more money because of what I was told and the way it did work..