Yes, I agree that greyhound racing should be banned industry wide. Greyhounds (and horses in fact) should no longer be forced to race for their lives. I have seen many rescued greyhounds and horses that used to be racing animals and they are worn down, in bad health, and want nothing more than to be a normal dog/horse.
If the actions of a few are becoming increasingly larger and more prominent then yes it should be banned if harmful things are happening even if it's not with all of those involved with greyhound racing. Putting animals on display in such a manner; you're bound to have those that abuse it.
If it was only a few people that were mistreating these dogs, it would not be a problem, but trainers and handlers in the greyhound racing industry have a pattern of mistreating dogs. Dogs are breed in such a way that they have major health problems and are treated poorly.
Although dangers exist in almost every industry, there are many good aspects of most of them as well. Just because a few individuals in the industry abuse certain privileges does not mean the entire industry needs to be punished. This is not fair to the people who have followed the rules.