Yup, first time I noticed them make that mistake. Not sure how often they do it but this time it worked out pretty good for me, got some extra trait items, crystals and sellable elixirs.
I also collected and opened star boxes on 8 different mules a day, which netted me around 1 to 4 cubic blades a day on average. One day I even got SIX cubic blades! Lots of good trait boosters and I think around 2 or 3 thousand superior crystals and around 4 or 5 hundred purple powder to Buy MapleStory Mesos. Also around 1 million mesos per day in sellable elixirs.
All in all a very nice event, plus got a lot of nice looking damage skins on my mules.
I also made a guide thingy to know which ones to do for easy coins...
Summeron - Complicated Wish - Cancer
Power Elixir, Orange Mushroom, Ear Plug Plead
Summeron - Perfect Pair - Gemini
Buy 100 Lemon, 100 Orange, and 100 Apple
Wintersia - Wetwork - Aquarius
Buy 200 White HP potions and 200 Blue MP potions
Wintersia - A Hidden Talent - Sagittarius
Weaken enemies, put in bags
Springtean - Papa Don't Charge - Taurus
Autumist - Higher Ground - Scorpio
Springtean - Minar Monsters - Aries
Springtean - Making Friends - Pisces - 6 min with 2x and spider
Autumist - Confessions of the Rich and Famous - Libra - 10 min with 2x and spider
Autumist - Everlasting Youth - Virgo - 9 min with MS Mesos and Spider
Summeron - I'm Not Lion - Leo
Wintersia - Lost Innocence - Capricorn