Perhaps where you live. In a town of 50,000 finding something to see is a chore or the price is ridiculous. I bought an Omron strapless HRM late last year. The only one I could find in town was $50 at Walmart. The same item was $25 from Amazon.
My worst experience was after I bought a car without a radio. It was a new model so the dash kit was also a new design. I went to the leading car stereo store in town and selected a radio. The salesman said they didn't have the kit and would give me a call. Okay. A couple of days later, he calls to say there isn't a kit but they might be able to modify one. Meanwhile, I'd been on a Toyota forum and gave him the manufacturer and part number. It was a Metra kit, one of the major providers. He said he'd order it from the his supplier and it should be delivered in three days. Okay. Three days later, I called. The shipment had arrived with no kit. He would try to order it from Spokane. Okay. Two days later, the Spokane delivery arrived, no kit.
I thanked him for his trouble through clenched teeth, went home, and ordered the radio, dash kit, and harness from Amazon. Two days later there was a pile of boxes on my deck when I got home from work and I installed the radio.
That's how it runs for most things around here and it isn't only Amazon. I went to a local archery shop looking for glue on target points. They're mostly into compound bows, not traditional archery. The guy said he could order them for me, but I could find them on the internet as easily as he could.
Back to books: I went into the B&N store looking for a title and she said she could order it and it would be a week or two at the full list price. I ordered it from B&N online for 10% less and free delivery to my door.
I really, really try to support the local brick and mortar stores but I'm starting to think they all have a death wish.