That isn't really true. I've never had people who were from my area of the country or really too close. You will sit with people from all over.
What they "try" to do is sit couples with couples, singles with singles and people of in the same age range.
I emphasize "try" because there are always instances where they can't or don't match too well but you can have fun with just about anyone. I think some of the most fun I've had is with people who were older than I am.
The least fun was when my wife and I were with a family of six and we felt sort of like a fifth wheel but we still had fun.
Regardless: My wife and I love open seating where we can pick our time and venue to eat. I have no problem sitting with someone new each night. It's sort of fun. The standard questions of "Where are you from?" "What do you do?" are over quickly and you can either have more in-depth conversation, light banter, or no conversation for the rest of the evening. It is also nice when you can do a table for two. After 27 years my wife and I have no problem having a fun conversation.
Take care,
Mike