Actually, building a critical mass of streetView-like data can happen while having other goals in mind.
For example, I live in São Paulo and I'm a member of OpenStreetMap. Every time I ride in a bike lane, I take photos of it with mapillary, so it gets way easier to map them.
By the way, the OSM coverage of bike lanes in São Paulo, because of the help of mapillary, is the best one in all maps available (even the city hall ones)