What is interesting is the could rule that the states have the right to restrict granting marriage license to same sex couples, however, they don't have the right to not recognize a same sex marriage performed in another state.
The court asked the parties to brief these two questions:
Does the Fourteenth Amendment require a state to license a marriage between two people of the same sex?
Does the Fourteenth Amendment require a state to recognize a marriage between two people of the same sex when their marriage was lawfully licensed and performed out-of-state?
Other states do not have recognize anything from another state. California does not even recognize the fact you have paid state tax in another state thanks to the multistate compact. California requires you pay California state tax in addition to the other state in even if you are incorporated in another state. California does not recognize driver's licenses from other states either. Washington now allows recreational use of marijuana, but that does not mean you will not get in trouble if you are a Washington resident smoking pot in another state. The main point here is marble cake federalism. http://www.apstudynotes.org/us-government/vocabulary/chapter-3-american-federalism/
The States were given sovereignty over many things to prevent the federal government from becoming too powerful. The states can in fact refuse to recognize other states laws.
At the present, however, that could all change with the ruling. The ramifications of this ruling can be very widespread.
What California does is tax you on your total income for the year even if that income was made out of state if you are a resident of California.
California does recognize driver's licenses for other states, however, if you become a legal resident of the state you do have to obtain a California license and that is true in all states. The time frame is usually thirty days. If you are just visiting the state you do not have to obtain a California license, your license from your home state is valid.
Your comparing one state legalizing the recreational use of marijuana to another state not legalizing it to gay marriage is absurd.
With the passage of time when have devolved/evolved from a union of 50 country states to a country of 50 states.