I'm not surprised. Keep in mind that most of the GC stores are manned by relatively young people that have little or no technical expertise, very narrow musical experience, usually only a single instrument, little or no retail sales experience, and I seriously doubt they are paid very high, so there tends to be a high rate of employee turnover. We have several independently owned music stores in Maryland that have been around for more than a half century and continue to do well. Their employees are very knowledgeable, have a lot of technical expertise, sales experience, and they take care of their customers. Granted, their prices may be a bit higher, but usually not that much higher than GC. Most have their own service departments and the vast majority are factory authorized service centers for much of the equipment they sell.
GC will go the way of many other similar businesses, and for the same reasons.
Gary