I see where you are coming from but there is a difference between being prepared to defend yourself, yes I am, and the gp's hypothetical situation.
the GP wants to provoke a reaction.
If you poke a dog with a stick it may well bite you and you may have to kill or injure it as a consequence.
when the westboro baptists decide to picket a funeral they are goading for a reaction in order to drag someone into court.
The fatal shooting of Trayvon Martin by George Zimmerman took place on the night of February 26, 2012, in Sanford, Florida, United States. If George Zimmerman hadn't ignored the Police directions to leave Trayvon to them and goaded Trayvon into fighting with him George wouldn't have been forced into shooting and killing Trayvon. Legally George was in the right because Trayvon did the wrong thing by physically attacking him but George set the ball in motion with his reckless or premeditated actions. Was he stupid or calculating?
I think you know really it's calling looking for a fight. Something the law doesn't seem to comprehend very well except perhaps Judge Judy, "but for this , that wouldn't happened" she often gets it spot on. She wouldn't condone punching him in the face, you don't take the law into your own hands, but he would get nothing if he sued the guy who got him kicked out.
The gp knows the gut reaction is for someone to punch him in the face, which if anyone was to do so, would tend to see him winning in court even after pounding on his assailant or shooting him as suggested by another poster. Cooler minds wouldn't take the matter into their own hands but look for a third party to resolve the situation.
I have in the past worked as a club doorman and been that third party. The job is not about breaking up fights and throwing people out but preventing these situations occurring. Once they occur well innocent bystanders can get hurt, you ruin the venues reputation as a safe place to have a good time ect.
So what you do is have a word with the trouble maker explain to them that they are creating a problem, everyone's having a good time, I don't want to have to ask you to leave but if you persist... to which they generally agree to be more pleasant and then you keep an eye on them for the rest of the evening, generally their buddies will be quite persuasive and keep him from drawing my attention again. Rarely do you ever need to back that up with the use of physical force.
The GP seems to be a bit of a socio-path, has trouble comprehending how others feel, that doesn't make him a bad person there are a lot of brilliant minds round here who relate better to computers than people. I mean just look at his reaction to my original post he now thinks he is the victim :). At a conference I expect most people would just complain to the organisers or ignore the "glasshole", thats a perfect term. After all who wouldn't expect to get fired or at least reprehended by their employer if they punched another companies rep.
In a wider situation, a bar for example, reactions maybe physical. Most of us are too polite to actually do anything about the Glasshole, but I wouldn't be surprised to hear a cheer or a round of applause as he gets kicked out or punched.
Really what I was trying to get through was that the advantage of having some ones details come up on google glass are out weighed by the negative perception of being a glasshole.
A lot of conferences may have name badges you could always discreetly google the name , discreetly. Far better would be to do your homework first know who you want to meet and a bit about them, those you meet for the first time, write the name company and context down as soon as you get the opportunity. You really don't need to know about all 2000 or so delegates just the ones that you feel are going to be useful to know.
People will be genuinely flattered if you remember who they are and a bit about them and have a genuine interest in what they do and who they are, however if its obvious that you just looked them up, it will be a negative reaction. Which is why Google Glass, is not a good tool for that kind of situation. You can also know too much which also gets a little creepy especially if they haven't told you that information themselves. You could ask a question or relate something that might cause them to volunteer that information if that is useful to you but tread carefully.
To be fair a lot of people will cop on to the fact that you researched them prior to this 'chance' meeting but it's still flattering and an ego boost. At a recent staff meeting I got a big round of applause after the boss said something nice about my work, made me feel good but it was quite meaningless. They would have applauded anything really it's just what was expected of them.
Anyway to go into a situation looking to press some ones buttons is not the same as being prepared to defend yourself against a physical attack. I am perfectly capable of defending myself if need be, I just don't look for situations to cause the need to arise.
Merry christmas to you, I hope your having a great family day.