To be more precise, I smoke filter pipes (cobs) occasionally. I never use filters, however. :heart:
It takes a real masochist to be diligent with filters, I've noticed--especially the 6mm paper (Medico/Grabow) type and the 9mm charcoal nonsense. Changed after only a few smokes, sure--I get that they might appeal to folks if they like fussing over such things. I can't tell you how many guys walk into my local pipe shop and say, "I'll be darned if my pipe ain't clogged!" The worker then removes the stem to find this black, reeking, dripping, horrid cylinder of nasty. A few even asked if "lifetime" filters were available. :lol:
The 6mm balsa Savinelli-type triangles have their place in some guys' hearts, but maintenance is required.
Beyond the idea that filtered pipes started catching on at the same time filtered cigarettes were touting themselves as "healthier" alternatives to the normal unfiltered, major pipe manufacturers in the mid 1950s (or so) decided to tag along with their own filters. It has also been suggested that cheaper pipes featured this to compensate for bad design and rushed manufacturing that led to excess moisture.
Bamboo shanks do indeed wick away moisture; the same principle with cobs and their hardwood shanks (no, the shanks aren't made from cob--they're just printed to look that way). Brigham and their "rock maple inserts" achieve the same goal, I presume. Though in the case of Brigham pipes, I believe the inserts can go quite a while without much trouble if kept clean. I have no idea as I've never owned or smoked one.
They are simple filters, not catalytic converters--they indiscriminately filter out everything in the smoke to some varying degree, and to my senses, the good stuff in tobacco, as well.
8)