For about a year now, I've been doing something that I want to encourage all of you to do as well: wait for the person behind the counter (whatever counter that may be) to ask, "May I help you?" Over the course of the past, say, ten years, this polite and once ubiquitous custom seems to have gradually disappeared. But it shouldn't disappear--we're all still humans, aren't we? We still need to relate ourselves to one another, right? So I have resolved to not place my order (etc.) until I am asked.
This decision has, at times, resulted in long, nervous, awkward periods of silence--situations in which the person behind the counter and me stare at each other in an intense battle of will. It has also resulted in disdain from both the service worker and the other customers in line. But I don't care--I'm trying to make a point. Besides, it's fun dammit.
One thing to remember when you do this is that even though you're "fighting" something that's wrong, you should always remain polite. Being mean defeats the purpose. So, try this little social protest for yourself. You'll walk away with a wonderful sense of victory and tingly feeling of righteous indignation.