- It's common for global manufacturers to sell products at different prices depending on regional market conditions. So EU distributers may get better pricing than US distributers.
- Some retailers may be able to purchase products cheaper because of volume or preferential relationship.
- Most commonly, the products beings old are actually OEM products originally sold at a significant discount to a bike brand (who have massive minimums, arbitrary product mix requirements - think a mountain bike brand buying road parts because that's the "package" Shimano sells to get favorable pricing, and big incentives to prevent them from purchasing from SRAM or some other parts manufacturer). The bike brand takes its excess parts and sells them "under the table" to a retail outlet (that they may have actually discretely partnered with at the outset).
My opinion is that yes, Shimano, specifically, doesn't care about brick and mortar retailers. Shimano considers it a relic of the past and are partially unaware (or apathetic) of the reality that their actions and distribution model is accelerating the death of the brick and mortar shops. That said, Shimano USA might care about US brick-and-mortar retailers, but they don't have enough influence to prevent Shimano Global (Japan) to affect any real change.
Shimano has seen steady growth, so they have no incentive to change. But that growth has been at the expense of the very partners that played a significant role in helping them gain market dominance.
I'm generally of the opinion that, at least in the bike industry, the shops and online outlets selling massive volume at discount aren't really in any better financial shape than their mom and pop competitors. When I first got into the industry I was regaled with stories of success of competitors like The Clymb and how they were 'killing it'. Turns out, the only thing they were killing was themselves. The Clymb, despite assurances of their brilliance, sold back in 2015 for $100,000 despite millions and millions in sales (the buyer assumed 18.5MM in debt) - https://www.oregonlive.com/silicon-forest/2016/01/the_clymb_...