I can only speak for myself... I've always treated workers as real people. I never worked a retail job but have several friends who did, and I heard a lot of stories of shitty bosses and entitled customers. Even if I hadn't I would treat people properly - my parents tried not to raise an asshole.

But, some of the stories my friends told were of obnoxious, slacker coworkers who took delight in messing with customers, and who felt that it was everyone else's fault that the world hadn't given them all that they expected.