I will be characteristically long-winded and evasive and say I think it all depends on what you value in your pipe smoking. Flavor is very much a major factor in what pipes I choose (to say nothing of the tobacco itself). Now, do I go as far as to dedicate individual pipes to specific blends? No, except for one lone cob which happened largely by accident and of which I will explain later.
I already have the PAD and TAD that have afflicted so many, and though my collection is modest, it is something bordering on ostentatious for someone of my modest budget. To me, to convince myself that I need a specific pipe for each specific blend is to introduce some rather contrived reasoning to my spendthrift ways. The sole exception I mentioned is a MM cob that was my first pipe and I smoked so much Cult Blood Red Moon in it that it still carries the cherry aroma and stain to this day. As such, that pipe is for when I need a cherry sugar bomb, and nothing else. My other cob is dedicated to other aros, particularly the goopy or codger blends. I find the natural sweetness of cobs gel well with aros, and the mess they leave is not a big deal to me when left in a $20 cob as opposed to a $150+ briar.
Now, I do have pipes that will help me explore certain blends in better fashion? Yes. I have a meerschaum I like to use when first having a tobacco blend I never had before, especially if it has a complex character. The neutral profile of the meerschaum makes it easier for me to get all the notes of the blend before trying it later in a briar. I also prefer my larger pipes for certain blends, especially those heavy in perique or oriental, as I find those blends open up more willfully when they have room to stretch, as it were. Burley-forward blends are always smoked in briars, as the taste they impart goes well with each other, especially in a medium sized bowl. Overall, ghosting is not a major issue for me, and I'm dutiful in cleaning my pipes, but I do try to avoid putting myself in a situation where ghosting could be a concern.
But more important than the flavor, for me at least, is the ritual. Pipe smoking is part of a private alchemy where I transmute the baser things in life, i.e., loneliness, confusion, and restlessness, into the purer things, i.e., solitude, clarity, and contentment. Sometimes, all I need is my pipe and some virginia, and little else. Other times, I have my favorite music on, a book at hand, a pale ale, and a particular blend and pipe in mind. And that is the primary motivation for me when choosing a pipe. What calls to me in that moment? I love to not just smoke my pipes, but to look at them, hold them, clean them, to see how the smoke leaves their chambers in swirly spires as I puff away. The whole point is to bring myself to somewhere better, to retreat into my own soul. The pipe is an implement I use to achieve that state of mind. The flavors are naturally very important to me; I wouldn't smoke if I found it distasteful in the literal as well as figurative sense. But modern times are demanding and fast, and the pipe is my relief from such demands.