Sometimes it's just a name tag. Other times it's a badge, color-coded to what your professional niche is, or what your convention status is. If that networking promotion doesn't sound like something straight out of a single's party, I don't know what does. The exact same thing occurs at a singles party, although modesty precludes too close an examination of this context. While you're out looking for that business partner, the prowling starts to resemble the baser parts of a single person's mating ritual.
Looks are still important, though the emphasis can slip to the cut of one's suit more quickly.
Business cards are collected and fancy titles savored. All the better if you partner with the CEO, instead of a programmer. This deepens when Venture Capital and potential investors enter the business networking event. That is to say, they want to be taken out for dinner and bought some jewelry before they stop returning phone calls. These people are looking for a ring.