While the video doesn't explicitly say what inspired these guys to build a snowboard with what appears to be car suspension springs, it doesn't seem like the most ridiculous idea in the world. Springs could hypothetically enable boarders to pop harder and land more smoothly. Perhaps the key to achieving futurespin is using advanced techniques like spring-loaded equipment.
It appears that our intrepid tinkerers chose springs so large that human bodyweight isn't sufficient to compress them, and so they ended up snowboarding on stilts. However, four smaller springs beneath each binding might be a way to maintain stability while also reaping the benefits which springs could provide in terms of pop and landing. We won't be testing out this theory, but if anyone has a beater snowboard and time to spare we'd love to hear how it goes.