I've read the other comments with interest because I get so sick of that stuff, too. I don't need all that in my head, and I'm a grownup, not a kid!
The thing to do at home, of course, is to turn the television off - you have a lot of suggestions for alternatives, if you want to try them.
When I walk through stores, I just have to ignore what I see. They don't care how I feel; I'm not their target consumer, and neither are your children. So we don't count. That's the way it is.
So the garbage may be there, but I don't have to have anything to do with it. Neither do you. You could always talk to the store manager, even though it may not do much good. If your children are with you, you need to have a remark handy that helps them learn what to think of what they see.
Your mention of television in the doctor's office brought back a memory! I had to visit the hospital every day, years ago, for radiation therapy. The waiting room constantly had the television on. I thought at first that perhaps it was required! Maybe there was no off button. But when I happened to be waiting by myself, I found there was a button and I'd use it.
When there were other people there, it was... interesting. There would be an AWFUL show on, and if there were just two or three others waiting I'd ask them, "Are any of you watching this show?" They'd say, "No..." "Oh, no, that's a terrible show..." So I'd say, "Well, why don't we turn the thing off?" Invariably they'd say, "Oh, no, leave it on..." "Oh, it doesn't bother me that much...." "No, it's not our TV so we shouldn't touch it...." I had to conclude that either people are totally tied up with TV, or... it's just too uncomfortable not to have some sort of noise on.
(On the other hand, I walked into the same waiting room one morning and saw, on the same TV, people literally running for their lives. That was how I learned about the Oklahoma City bombing.)