Every exhibitor ends up choosing a lead capture method, whether deliberately or by default — usually whatever the show organizer offers unless someone actively decides otherwise. There are really three distinct categories, and they differ enough on cost and what they actually capture that the default option is not always the right one for a given booth.
This compares the three approaches on the dimensions that actually matter for a follow-up-focused exhibitor: cost, who owns the data, and what signal beyond a bare name and title you actually get.