Why can't we convert/add bike lanes to sidewalks?

Sidewalks are largely unused infrastructure because it's impractical to get anywhere on foot. Sidewalks are usually fucked up and have random twists and turns. Putting bike lanes next to/convert sidewalks with blacktop paved paths would increase safety for cyclists and keep the cagies happy because they can keep their car-dependent suburban shitholes and there would no longer be leotardfags shaking their ass on the roads.