It makes absolutely zero sense to me too, but what do I know, other than that the idea seems to be that snapchat, like Facebook before it, is seen as the drug that compels today's generations.
It was newspapers, radio, and TV before and now it's Snapchat after Facebook. At least I think that's the reasoning. If you can capture people's minds and compel them to put real money into people's pockets, then you can capture the whole of society.
If you think about it, we are somewhat still in an equivalent world where there were only a few radio or TV stations, i.e., Facebook, Google Ads, Snapchat, etc. who command the minds of ever more people in the world. It's a de facto cartel monopolized market not unlike the Robber Baron period of American history, where few dominated the vast majority of economic activity with their stranglehold.
Unfortunately, due to the inherent network effect of the internet and technology, it will only ever increasingly become a race for who can steal away the vast majority of human minds of the ever increasing digital human herd.
Snapchat will have its day as Facebook starts atrophying and contracting as people shift to Snapchat, then something else will come to poach away a future generation that is then ridden to poach away minds from Snapchat. It will be an ever repeating cycle of one company stealing away the vast majority of minds from the last company. At least as long as certain conditions are true.