Northern Lights, the delightful independent bookstore that was an anchor, for many years, at Canal Park up in Duluth, was the first I'd heard to complain about the problem: Customers browsing the shelves, leafing through books, choosing what they wanted--and then scampering home to order the books, cheaper, online.

"We're really a showroom now for books," said owner Anita Zager last December, as she announced that her store was closing after 17 years.

A year ago, the folks at Amazon might have shrugged, saying that's just capitalism at work. But this weekend, they're taking the gloves off.

In a press release sent out on Tuesday, the folks at Amazon have announced a new free price check app for smart phones which will, they say, ensure that "a deal really is a deal." And tomorrow, they'll give you 5 percent off, up to $5 per item (to a maximum of three items), if you'll use it. They're asking you to download the app, take your phone into a bricks-and-mortar store, scan the price information on something you are interested in buying, and then scamper home and buy it from them.

You'll get the bonus from Amazon on Saturday if you do this, but they're urging you to use the app year-round, even without the bonus, thus "allowing all Amazon customers to get the lowest prices." (And thus, of course, allowing Amazon to collect all kinds of sales data from all over the place, with no effort.)

It is interesting to note that Amazon's offer applies to electronics, toys, music, sporting goods, and DVDs. It does not apply to books.

Northern Lights Bookstore in Duluth, which closed in February. Too many customers were browsing the shelves but buying online, owner Anita Zager said. Photo by Alfred Essa.

It is also interesting to note that it is indie bookstores that are fighting this the loudest. It was, of course, through selling books at a high discount that Amazon first launched its empire.

Facebook pages have been launched. Petitions begun. Objections voiced in editorials, on social media. (see #occupyamazon on twitter), on blogs, in statements and even by politicians.

Oren Teicher, CEO of the American Booksellers Association, released a statement, saying that while they were more disappointed than shocked, they see this as "the latest in a series of steps to expand your market at the expense of cities and towns nationwide, stripping them of their unique character and the financial wherewithal to pay for essential needs like schools, fire and police departments, and libraries."

Bookstores, especially independent bookstores, have long objected to the advantages that Amazon has over them, including serving as both distributor and seller, which cuts their costs, and, especially, the fact that Amazon pays (and therefore charges) no sales tax in most states, including Minnesota.

Bookstores have launched a counter-attack: "Occupy Amazon," in which they urge everyone to buy local on Saturday and boycott Amazon, at least for that one day. Some publishers have joined in.

So what'll it be, folks? Pay a little more to keep independent stores around? Or is all about the cheapest possible price? Which way will you be leaning, come Saturday?