It would be fair to say I have a problem with Buffs. To put it simply I think they are great and I own loads!
I simply find them really useful, more versatile than a bandana, a greater range of colours and ultimately loads of ways of using them. They are really useful to wear under your dry top to help keep your neck warm and catch the odd drip of water that may make it past your neck seal.
As well as being a great bit of wearable kit I have also used Buffs for cleaning my camera kit/glasses, first aid and all manor of things in-between.