"We're doing 3000 seaters before that we never played anything more than 1000"

This quote by Kevin McDonald is describing the dimension of the venues they are playing in. He is saying that they are now playing in venues that can seat as much as 3000 people, whereas prior to they were just playing in places that might seat up to 1000 individuals. This recommends that the band has grown in popularity as well as is now able to play in bigger locations. It also implies that the band is currently able to reach a larger audience as well as has ended up being a lot more effective. This quote is a testament to the effort as well as devotion of the band and also their fans, as well as is a suggestion of exactly how much they have come.