As far as I know , you receive a few free gachapon tickets for leveling up. While I was leveling up one of my character from lvl 10~18 by doing the NLC mayor quest , I leveled so fast that it must have jammed up the inventory of the cash shop . There are only 2 tickets left lying in the cash shop when I enter it. And so on I no longer get any gachapon ticket after leveling up .