The artisan baker, like the brewmaster, takes great care in choosing the types of grains, sugars, and yeast that are used for each artisan bread. Keeping starters going for years, that pull the wild yeast out of the air to create regional sourdoughs. Blending together starters with poolishes to create complex French and Italian. Developing wheat starters and poolishes to coax the flavor out of the grain to create the artisan's unique Honey Wheat, Spent Grain, German Rye and Multigrain. Gently working the soft Ciabatta dough, that spends the night in a bath of extra virgin olive oil. The two-day process of the biga that creates the desired texture and flavor of the Neapolitan dough, for hand tossed pizzas.
Commercial bakeries are mainly concerned with pumping out as much bread as the machinery can produce. Grocery stores buy frozen, pre-shaped, dough that they then thaw and bake. (Baked fresh daily and made fresh daily are not the same!) For the artisan baker, the combinations of starters, poolishes and pates can cause a batch of bread to take anywhere from 12 to 48 hours. To the artisan baker it's not about pumping out as much bread as is possible, it about creating the best bread he or she can bake and then trying to make it even better the next time. Each loaf is shaped by hand and baked with care. Some breads are steamed while others are bathed in buttermilk. Each bread is given it own unique look to compliment its unique taste.
If you can't meet the artisan baker, it is not artisan bread.
Many chain grocery stores and chain bakeries use the term "Artisan" to describe their bread. That would be like a large commercial brewery claiming to make "Microbrewery Style" beer. The consumer would know better when it comes to beer.