How can I identify quality bacon? I see bacon in store that varies widely in price. From the bulk ends and pieces packed in a solid block to thinly cut off-brand to expensive thick cut bacon.

Some of the differences in quality are obvious. The really cheap brands are thin enough to see through and very fatty. I haven't done side-by-side taste tests to judge for myself how bacon at various price points compare.

What makes premium bacon more expensive? Is it simply a more meaty cut or is the smoking process more flavorful?

The other side of the question is- How can I identify good bacon that has those characteristics? Is it really just you get what you pay for and inexpensive bacon can never be good?
Just look out for artificial flavorings; a lot of bacon comes with artificial "hickory" or "maple" flavors, which are disgusting and often taste like chemicals.  The better bacon won't include such things.  Nitrate-free bacon is important if you're sensitive to nitrates.  The fat content is more of a matter of taste than a hard-and-fast rule; personally, I like a fair amount of fat because I like to cook other things in the rendered fat!  Same for the thickness.  If you like very crispy bacon, you may want your bacon slightly thinner than the "thick-cut" styles that command a price premium.