I think your headline is a bit sensationalistic and I wholeheartedly disagree with it.
I agree with Reilly's comment that a business card is not a lead though. Of course it isn't. It's only worth something when it's been qualified which is much more cost effectively done if it happens when the contact is made rather than following up later on.
I completely disagree with Tsivandis' comments that ROI on events is just not there though.
ROI depends entirely on the objectives of your event which, in most cases \(or maybe all cases) a client will define. Using financial return in relation to the investment to make the event possible is just one way of looking at this. ROI is more tangible \(or conventional) when it's a sales orientated event - e.g. retailers attending a product launch and they'll place orders there and then, the value of which is heavily influenced / dependant on the quality of experience they've had, giving you a clear financial ROI figure. On the consumer side, things are also clearly measurable, especially when they're combined with an in store promotion or people can purchase from your activity.
However, many events are not directly related to sales so the ROI will need to be defined in different ways that relate to your objectives and how close you are to achieving them or how much you have exceeded them. A return on investment can be a change on perception calculated from qualitative research or having a certain proportion of the invited audience attend an event or how much that audience wrote about the event they attended.
ROI doesn't have to be an immediate financial reward, the return can be so many more things and frequently not an immediate financial reward but a medium to long term payback like \(as Tsivandis stated) improving your brand image which IS a return to your investment and can be measured.
