CRI was never intended for the GA market. It was put in to allow commercial single engine operators to do the required training in a SPA.
Which is the reason why in some ways pre EASA the CRI is less restrictive than an FI. They can train at night without doing anything extra and they used to be able to do aero's as well.
But because of the way the UK ANO is set up a CRI in the UK was actually and extremely useful rating for minimal cost. So people started getting them. I wouldn't be surprised if the majority of CRI's for SEP are in the UK for Europe.