I just wrote a long post that was eaten by the internet…anyways…
In short, 'chasers are not often in a position that they need to be “rescued” or cleared out of a barn quickly like horses on sites such as CANTER.
My boss works for one owner who has a lots of 'chasers, and most of those end up coming back to the farm (at least from the one trainer) when they are on breaks or when they are done racing. She just outrode at the Grand National on Saturday on one that was a former hurdle stakes horse. A few others this owner has have either stayed with trainers as hunters, come back to the farm, sold as foxhunters, or donated.
If you look at a lot of hunt clubs, many of the staff horses will have been donated after retiring from racing. I know Piedmont and Green Spring have a few.
A few years ago, the Virginia (North American?) Field Hunter Champion was Gol Lee, who is a former hurdle/timber horse that I galloped and hunted prior to his retirement from racing.