For two UK charities I've worked with, the reason is that they've been tempted by the siren voices of Google.
Google offer a tempting deal to charities: free mapping, and the chance to get your content hosted on Google Maps. So, for example, Sustrans' cycle routes are now integrated into the Google's UK mapping data.
This seems to appeal particularly to the higher-ups. The developers/GIS team may be more au fait with OSM, but when the marketing director says "We have the choice of getting our routes publicised for free on Google, or... what's this obscure 'street map' site you mentioned?", it's hard to convince them. (I did try to persuade one such charity to switch to OSM-backed mapping, but the answer was "Google is a corporate partner of our charity - we can't be seen to switch away from them".)
It's a great shame especially because, as you say, the tooling available around OSM data is so much more powerful than the Google Maps API could ever be. But I'm not too worried: it'll come in time. With OSM powering more consumer-level sites by the day, it's getting easier to answer the marketing director's question.
I have a similar experience regarding choosing OSM over people's go to mapping service (which looks completely free to them because Google doesn't ask them to pay). One way to deal with it is just not taking about the decision when they don't even know all the options. Just make it work and they'll probably be fine with it.
Google offer a tempting deal to charities: free mapping, and the chance to get your content hosted on Google Maps. So, for example, Sustrans' cycle routes are now integrated into the Google's UK mapping data.
This seems to appeal particularly to the higher-ups. The developers/GIS team may be more au fait with OSM, but when the marketing director says "We have the choice of getting our routes publicised for free on Google, or... what's this obscure 'street map' site you mentioned?", it's hard to convince them. (I did try to persuade one such charity to switch to OSM-backed mapping, but the answer was "Google is a corporate partner of our charity - we can't be seen to switch away from them".)
It's a great shame especially because, as you say, the tooling available around OSM data is so much more powerful than the Google Maps API could ever be. But I'm not too worried: it'll come in time. With OSM powering more consumer-level sites by the day, it's getting easier to answer the marketing director's question.