I run across this in my business too (nothing to do with cues or billiards). A handful of bad businessmen, and just plain old crooks, makes all of us look bad. With the internet and forums, the train wreck experiences blow up like crazy and dominate sometimes.
You can search high and low and will not find one negative comment anywhere about my service and customer commitment. Not everyone loves the product, but everyone loves my service and reliability, and I'm fortunate to have built a very good reputation.
Doesn't matter. I still see people asking questions equivalent to, "Does this large company production product sound like John's?" because people just don't want to get burnt. The serious builders like me get lumped together with the clowns because their scorched earth poor business practices leave a lot of extremely unhappy and very vocal customers behind. The happy customers usually just keep to themselves unless they're deliriously happy. For every 1 of my customers that says something nice, 30 more say nothing, or possibly just sends me a little thank you note. Customers that get screwed, on the other hand, are almost certain to say something.