Some people familiar with the venue already explained that it means nothing. The more expensive tier is simply more expensive. There are more limited quantities of tickets in the cheaper tiers, but if those are still available, you should go for those.

Paying more for "chance to meet artists" is only a thing in mainstream pop music. It doesn't apply with indie music and certainly not dance music.

Grimes used to meet with fans outside after some shows (you could never know in advance), but she has never done a tour where anyone paid more for a guaranteed meet and greet. Given her recent observations of fame, no one in the public will probably have any chances to meet her in the future, regardless of how much they pay.