Thousands and thousands of people? Mark and Tom are the blink live show. A huge number of concert goers really don't notice the drums between a good drummer and an excellent drummer, especially blink fans. I've seen them live with scott and travis, Mark and Tom made fun of them both the same way and put on a really good show, the biggest difference I noticed is travis gets a long drum solo now (granted i was much younger when scott played.) This is Blink 182 not Led Zeppelin.
Travis Barker is a great drummer and tons of blink fans enjoy seeing him live, it will be a huge letdown if he's not able to make it. I don't understand the point of bringing in Led Zeppelin, that holds no relevance to the conversation.