I've got a couple of things working against me (flawed personality acknowledged, but set aside here): I travel perpetually solo for business. Any socializing with clients would result in immediate termination. Add in the fact that my wife died at 47, I'm destined to many years to solo dining. Fortunately, it feels like a completely natural thing now. If others watching me - or restaurant management - feel uncomfortable or that I'm breaking some sort of cultural norm, they're going to have to get over it.
It is interesting that the Opentable reservation system offers more choice to parties of two than parties (is it still a party?) of one. Then again, I understand the cost involved.