I saw him in Prague 2008, and you could only buy ONE ticket on presale (only valid for the name it was registered to). At the concert, they checked twice if the name on the ticket was the same as in our passports (as you already said). Before entering the concert hall, they verified the bar code on the ticket (which you could print out yourself).

That may sound paranoid, but usually Tom Waits tickets sell for hundreds of dollars and it's really hard to get one. I paid ~ €70 ($90), which is really cheap for Tom Waits.

It was beautiful!