The official response suggestion from Drew Cross does not work.

When you have multiple blogs in a hierarchy and click the “Show all blog posts on the site, not just the ones under this blog,” it actually pulls all blog posts from other pages, not just the ones from the parent blog and the sub blogs.
There should be an option instead to “Show all blog posts in this tree/parent page/sub page.”
Please give us an option that will work as this response was intended.

For those who are comfortable editing code in the template for their event page, (it’s fairly simple if you are careful not to change other parts of the code)
here are instructions on how to reverse the order of the tickets:

1. In your event page, click template.
2. Use the find search field for the string “ticket_level”, it should look like this:
{% for ticket_level in page.event.ticket_levels %}

3. Add “reversed” to the code so that it looks like this:
{% for ticket_level in page.event.ticket_levels reversed %}

4. Save and publish and your tickets should show up in reversed order!