Seat fillers do exactly that-- fill seats!
Occasionally, 1iota is hired to bring fans in to make sure that when that awesome camera shot pans over the crowd, there aren't any empty seats!
Seats can be empty because someone with a ticket is running late, in the restroom, not attending, etc. If you have a seat filler ticket, you will be directed by our 1iota team to sit in a seat until the person whose seat you're in returns. You will then get up and return to the 1iota team. We will then place you in another vacated seat, or in our holding area until another seat becomes available.
Sometimes, the person whose seat you're in never returns! That seat is then yours for the rest of the event.