The don’t “just carry lower end”, but in general big box retailer’s listings *tend to skew toward lower-end lower-quality *(they would call it value-oriented) versus higher end.
The reason for this is that 1) They target unknowledgeable DIY consumers and 2) By and large, they don’t provide knowledgable sales staff. As a consumer you must then figure it out for yourself (based on packaging, internet research, asking in an SD forum etc).
In the absence of sales explanation (why product x is worth 30% more than product Y), consumers default to price. Typically not buying the cheapest but not the most expensive, all other factors appearing equal. Since no one is there to explain to you the features and benefits of the higher end product, they simply don’t sell as well in those locations. They carry them, just not as broad a selection as the value oriented products.
There are many examples of this when you compare categories like lighting, tiles, plumbing etc. The specialty stores in these categories will tend to carry both a broader selection of manufacturers, and well a a deeper selection of product from each manufacturer and a very wide range of price points.
As someone who has worked in consumer products, I’d say you need to ask yourself: 1) Is there a legitimate difference in quality of components? 2) Is the price & quality difference justified to me given my intended usage of the product? More expensive, higher quality is not always better for you personally.
We renovated our house a few years ago and went with higher priced high-quality stuff since we planned to live there a long time. We’re now renovating my late parents house and almost everything is HD or Lowes, we’re going to sell the house when we’re done.