As usual, most of the exhibitors and attendees at such events asked for his name card or contact details so that they can follow up with him. After all, these are leads that they can follow up with and possibly close a deal.
These same people are also eager to give out their name cards in the hope that he will contact them for more information.
Most of the times, he would receive a follow up email from those people who have gotten his contact.
For those he promised to send them an email when he ran out of name card, he would drop them a courtesy email.
Without fail, all the emails and the reply emails that he received include a chunk of information of the their companies and products/services cut and paste from their website or brochure.
Looks like a standard template they mass email out.