Average car buyers don’t buy cars based on the carmakers’ motorsport activities, or lack thereof. They simply don’t care one way or another. What these folks want is a lot more prosaic than the passion of motor racing and the pinnacle of motorsports. What they want is far more down-to-earth stuff than the sky-high horsepower of racecars. They just want their rides to be cheap and good – or better still, cheap and great.
F1 is not a factor for them, unless the automaker starts charging more for its road cars to subsidise its racecars. At which point, the potential car buyers would just walk away and patronise the next-best car brand, instead of wasting time and money on Formula “None”. 
Before, during and after all the hoo-ha surrounding an F1 Grand Prix, in Singapore or elsewhere, car buyers still ask car salespeople the same old questions: “How much? How much discount? Got leather seats? Got sports rims? Got free accessories?”.
They’re extremely unlikely to ask: “Got take part in F1?”.
