*sigh* Here we go again...
Trademarks are not necessarily exclusive, and while registering a trademark will go a long way in a court case, it will not guarantee a win. A trademark is simply what you are known as to consumers. Once upon a time, "Escalator" was a trademark. "Escalator"s became so popular that people began to associate "Escalator" with moving stairways. Since "Escalator" didn't protect it's brand, it slipped into generic usage and they lost their trademark. Now anyone is allowed to sell an "escalator".
This is why we have recently seen such a huge push from Xerox, Kleenex, and Google asking people to stop "xeroxing", "using a kleenex", and "googling". As soon as the usage of the word becomes a verb to the common person, instead of a noun, the trademark is lost. This is why companies will pour millions into branding efforts telling us to "Copy using a Xerox photocopier", "Use Kleenex brand facial tissue", or "Use the Google web search engine".
Additionally, Trademarks can be regional. There was at least one case of Kentucky Fried Chicken not being allowed to call themselves "Kentucky Fried Chicken" in Kentucky. Why? Because there was already a "Kentucky Fried Chicken" in town that people knew about. It didn't matter that some large company had the name also - the small guy was around first and was therefore allowed to keep the trademark in the region people knew them. (They would not have been allowed to open up a new store somewhere else though, as people in that area likely wouldn't have known about them but would know about the chain.)
The government will grant a trademark application to just about anything, as long as it doesn't already exist. It's up to the courts to determine if infringement has happened later on. In the case of something such as the game "Candy Land", which has been around for a long time, they would certainly prevail. (Unless they fail to protect their mark.)
