First off, +1 for checking the Scrum Guide!
The book answer would be that it says the attendees include The Scrum Team and with no extra qualifiers, it can be assumed that it means the whole scrum team (Dev team, PO, SM). But I'd hate to just give you the book answer, so in my time practicing Scrum, here are some of the benefits I've seen to including everyone:
1) No whisper-down-the-alley. If you ever played that game in school, you probably know that for every person a message has to go through, it loses details and gets distorted, regardless of how hard you try to get it right. The Sprint Review is an opportunity to close that gap between stakeholders and developers.
2) It creates ownership. When developers have to show their own work, they value it more. They also get more exposure to the effect their work and other team members work have on the overall product and fulfilling stakeholder needs. When they aren't there it sends a subtle message that it isn't their product to show, even if you don't mean to send that message.
3) It makes it important. Telling a developer that the review isn't worth spending at most an hour per week on diminishes the value of the review and other people notice (and let's face it, it's usually far less).
4) Questions get answered quickly. If either developers or stakeholders have questions, you can answer them on the spot and account for them in the backlog. In my experience, most teams I see not having effective reviews actually spend more time chasing answers down than they would have spent if they just all went to the review.
I'm sure there are many more benefits - those are just the ones that sprint to mind. Maybe other people can add some in the comments that I missed.