The court can find no right not to carry a gun either. The government is barred form denying gun rights.
Given the basis for the 2nd amendment (protection from tyranny), it's hard to figure how someone from Florida is protecting himself from tyranny by carrying a gun in Colorado. In fact, the reasonableness of the 2nd amendment would be undermined were resistors against government oppression were not, in fact, subjects of that oppression.
Nor does the case reach as far as the article implies it does. The article cites Heller as upholding "longstanding prohibitions," but in the cited content from Heller, the article reveals how this is a fantastically qualified sentence:
"...shall not cast doubt on longstanding prohibitions on the possession of firearms by felons and the mentally ill, or laws forbidding the carrying of firearms in sensitive places such as schools and government buildings, or laws imposing conditions and qualifications on the commercial sale of arms,In other words, the Supreme Court has upheld only certain reasonable regulations on the right to bear arms, one of which being the states' ability to require concealed-carry permits. The clear implication from the court is that the decision may have been significantly different if the plaintiff was one of the sheriff's own constituents.