+1 on the above. I don't have any special insight on what park run is like to deal with when you cross swords with them, I can easily believe whatever people say about it.
It seems to me that they're arguing from a position of considerable high ground though.
Let's imagine that Spokes arranged a weekly "cycle bus" style thing for kids to get to school. However many kids took part and put some kind of strain on public resources, I fundamentally disagree that they should be surcharged. It doesn't really matter if someone in Spokes is getting a retainer or Specialised are chucking in some sponsorship.
The way this has been discussed in the wider world, you'd think we've forgotten that 2/3 of adults in this country are clinically overweight...