Rick - I'm not suprised at all. It's part tradition, part habit. If you watch all of your heros play Martins then you will be tempted to get one too. One of the reasons I bought my D-18 was because Tom Paxton played a Martin. There are a lot of good guitars being made nowadays and most of them are very suitable for this style but it will be a long time before they make inroads into such a culture as bluegrass.