Does it indicate that because you can attribute its creation to someone, and that special attention was supposedly paid to this creation, that it is the best among your choices? Consider the possibility that House Blend may mean Economy Blend if it is the least expensive of your choices.
But, if the roaster’s brand name is prominent on the bin of produce, and someone’s reputation is riding on its taste, it might just be fabulous. Especially if it is featured and is not discounted, except when it is on sale.
I always ask the store owner or manager how it got to be the House Blend. Sometimes they actually worked with the roasting company to create something special. Then, there is ownership and pride attached, and you can bet you are going to get a House Blend of quality.