Alternatives to paper handouts in conferences
There is almost no reason to give out paper handouts any more.

Almost none of the conferences that I attend hand out anything paper other than an updated program, if that.  Instead, everything is either in a USB stick or simply online at the conference web site.  Conferences with full papers tend to give out a USB stick; conferences with abstracts tend to place them online.

And here is where I see the only reason one might still want to bring a piece of paper: if the conference is handing out USBs stick or some other form of program that must be produced many weeks in advance, then if you want to give your audience some piece of information to look at that was not available then, you might bring paper.  To me, however, that sounds like a relatively rare case and not something that needs preserving as a typical custom.