Our first trip (CSS), we were invited to the repeaters dinner I believer because we had booked a 10 night stay. That particular night there was also a wedding party present, of which only the groom was a repeater but the entire party of about a dozen were at the dinner. To me, this indicates there is not a hard policy about this so I'd ask when you arrive if its alright if your friends accompany you.
No, only repeaters can come to the repeaters dinner... they can enjoy a romantic evening to themselves while you are at the repeaters dinner. When they are repeaters at their next visit, then they can come. I'm trying not to be catty here, but, it's called the repeaters dinner because that's what it's for. If newbies can come, then why have it ?? It's a perk for repeaters. It's an incentive for them to return, which I'm sure they will! No problem mon.
The Repeaters dinner is reserved for repeaters. In fact, be sure that you are registered in Romance Rewards so that they will know you are a repeat guest before you check in. The reality is, they don't have armed body guards at the restaurants checking to make sure you have an invitation. However, your friends might find that they enjoy having dinner on their own while you enjoy the repeaters dinner.
We are at CN now. I have 50 people in our group and a few first timers were invited to the repeaters dinner. I'm not sure if it was a mistake or not. It was clear that management wanted to hear the opinions of people on cost and rates.