... or unrealistic shopper expectations?

No, it's the lack of competition allowing them to charge whatever they
want.

Lack of competition due to whose fault?

Why should I have to bargain with them by showing ads for items at lower
prices.

As the sayings go; Nothing for nothing, and If you don't ask you don't get.

I prefer buying in a store where I can see the merchandise. My
expectations
are that there should be a reasonable mark up on merchandise.

On a boat? Reasonable? Surely you're kidding.