Amazon, Uber, Netflix and Snap can become more valuable by earning more from audiences they already have. Amazon's ad revenue grew 26% to $19.8B last quarter; Uber's ads surpassed a $2.5B annualized run rate, growing roughly 50%; Netflix expects about $2.7B in ads this year; Snap's subscription-driven other revenue grew 85% to $316M last quarter. Investors underestimate how valuable that can become over time. x.comÂ