Probably can exchange some # of tickets for a token, which will allow you to change the job of your explorer character (as long as it is in the same category-eg.page to spearman)
At least, thats what it did for KMS.
I thought it was related to this:
November 13 - December 3
Accessible through the Lightbulb icon on the left side of the screen or by talking to Cassandra.
You will receive a RED Gachapon Box that requires a key.
In order to obtain the RED Key, you must fight RED monsters that randomly spawn every 3 hours.
You can receive a box on one character per account per day.
Exchange Ticket for Key & Box
I think its about starting out with characters of a specific lvl. I mean think about it. 30, 50, 80, and 100 are all possible levels that people have gotten in the past from events. So 3 tickets will get you a coupon to start out a character at lvl 30, 4 to 6 tickets will get you a lvl 50 starter, etc.