Saudi Arabia one of the most oppressive countries in the middle east and ally to the USA "the land of the free".
They aren't a great country and SA funds a lot of Sunni terrorists but they're a major trade ally and military ally in the region. It's better to have a friend, however bad he may be, then be alone when you charge in.
From what I've heard there is a massive trade deal that is/went down but I'd be interested to see if Trump could get SA to take in Syrian refugees so Europe can stop cucking itself over them
Besides, it's better to have Saudia Arabia as a stable ally in the Middle East, with Iraq and Syria in shambles and Iran as a religious state.
You realize those states don't accept refugees because those countries already repress political liberty, right? Taking in refugees from an active rebellion in a close country doesn't seem like the best move for your political stability. They also control OPEC (which fucked Canada, by the way) and as Steven said, they aren't hellbent on destroying Israel. Doesn't make them a 10/10 ally but it's more like 7/10, and in the mid east you take what you can get
Edit: Holy shit, anyone else see the deals reaching in Saudi Arabia? this is truly history