This is a subtle and often-missed point. In the markets where they are trying to acquire customers and become dominant, the "Uber-for-X" businesses have negative gross margins. But they will have surely demonstrated (or the investors really are fools) that, once they have saturated a particular market (ie, a region or city) they are unit profitable. The bottom line looks bad because these companies are growing so fast that their balance sheet is dominated by the markets they're aggressively trying to corner, which wipes out the profits from the markets they have already won and proven viable.