They've been spending like mad on growth, but underneath that is a real company. Uber is on track to draw 4 billion in revenue in 2016, more than double 2015. Uber is the next big tech giant, they've still got plenty room left to scale.
A real company how? They don't own anything. Everyone I know in NYC has between 2-4 ridesharing apps installed and they choose whichever one is fastest/cheapest. For a while that was Uber, but as they run out of money and have to start turning a profit, you can guarantee that won't last long.
And by "that won't last long," I mean that era has seemingly already passed. The quality degradations in the past few months alone in NYC have been serious enough for me to default to Juno whenever possible. I'm not saying Juno is sustainable either (I don't know), but so long as any ridesharing app is willing to burn investor capital at a loss, I'm willing to benefit from said loss. I have no allegiance to Uber and I doubt anyone else does either.