Is this a proven statement or a hypothesis? In other words, are you trying to get your first users or are you trying to get more users?

If you already have users who have succeeded with your product, I would suggest publishing detailed and attractive case studies with your earliest clients.

If you don't have users, then it's a tougher proposition. You need to get out there and get to know the restaurant owners who have early adopter personalities (willing to take a leap of faith). I don't have a lot of advice on how to do this, other than continuing to network. Perhaps offer some additional incentives?