I love that the laurel-purchased chests can contain skin tickets! But nothing I saw in the store (at least on mobile) indicated this until I happened to draw a chest that contained one. Even if there's something special about the drop chance like "only appears in place of a skin you already own", there should be something that tells players about it--it was a little discouraging to look in the store and initially only see chests that, for me, seemed to contain nothing new.
#Olympiad chests can contain skin tickets, but the store doesn't say so
vale pivot
frigid wolf
Previously duplicate skins would be replaced with 5x scrolls of a random legendary.
ionic yoke
I don't think the tickets are in place of skins you already own. I received a ticket on my captain side and I did not own any of the skins in the chest.
jaunty sinew
I have seen this as well, but your skin ticket counter is not going up. it could be a visual glitch and it is still the legendary scrolls.... or maybe we got nothing 
humble igloo
From my experience, tickets have definitely been given as dupe skin replacement, instead of legendary scrolls. Both in the chests, and skin gifting rewards.