Because that's not really close to what happens. Obviously, The Echoes ceremony is live broadcast and everyone can watch it. It's basically an award show... do people have a bad time at the ESPYs if they "don't know anyone?" Of course not. And while obviously this isn't a "real" award show, in the past few years they've had people like Skylar Diggins and Mike Mayock come host it, so it's not some team manager up there just reading off names...
...and with all of that being said, that's only about 1 hour of the whole weekend.
The rest of the time is getting to interact with all of the current and prospective players (usually we have a ton of commits on hand) in a festive and fun atmosphere. Whereas an OV over a game weekend has both "work" and "play" components the banquet weekend doesn't have the coaches or players with divided attention. It makes for a great overall experience, and one where recruits can get plenty of face time with whoever they want. And seeing how proud/successful/happy the team & parents are simply makes a good impression. It shows the total package of what ND has to offer in action.