I don't know what you mean by "first class citizen". Perhaps you mean the royal family, of which there are a two or three thousand. Perhaps they get some kind of stipend but the average citizen does not.

When I was there the government did give a newly married couple a small grant of land to build a house. I don't know if that practice has stopped or not.

Saudi Arabia is a highly stratified society. The royal family is at the top, and then there are those that are friends of the royal family and those that are friends of these people and so on down. It is called "wasta". If you have wasta then you get promoted in your job, you never have to pay a traffic ticket and so on. If you do not have wasta then you are S.O.L. There are degrees of wasta. Some have lots of it, like the royal family, some have less and some have only a tiny bit while others have none. How high you rise in your job depends entirely on how much wasta you have and absolutely nothing else. But there is no "official" wasta. It is all under the table.

The Sunnis are also a rung above the Shiites. A Sunni will always have more wasta than a Shiite. Well, that is in ARAMCO and most of the rest of the country. In some towns where the Shiites are in the majority, they would have more "local" wasta than a Sunni. But there is no hard line between "first class" and "second class" citizens although there is a strong, but graduated class structure.