This may not be a 'popular' response, however ...
I'd rather donate cash, than my points - as I believe my $ is worth a $ to the charity - but a 'point' is valued at much less.
What value could a third-party place on 'points' ( to include points from other organisations as well ) ?
I've heard, that 'points' are valued at about a third of their value that the 'earner' may attribute to them, as they first need to be 'sold' in order for the gaining charity to be paid anything.
Somebody makes a profit - and it's not the charity, nor the 'earner' of the points ...