Are you willing to pay?
Yes, because it doesn't have to be a direct exchange of money.
For example I feed live data to Wunderground, Flightradar24 and several other smaller sites and in exchange they give me ongoing advertisement-free subscriptions to their services.
That costs me a few pence per day in electricity, on top of initial equipment acquisition, but neither of those costs is tied to one particular service. I could change from Flightradar to Planefinder or Flightaware, for example, and receive the same benefits.