You're right about the huge mark ups, campbellking. This is largely due to the very high cost of renting the shop space from the NHS or whoever owns the property.
Bring back the WRVS, I say.
"Bosses claimed the costs at hospitals were far higher, with longer opening hours and agreements with hospitals to hand over a percentage of sales, rather than paying ground rent....."
https://www.independent.co.uk/news/uk/home-news/whsmith-accused-of-exploiting-vulnerable-patients-over-prices-in-its-hospital-stores-10470036.html
A shocking demand for rent from a charitable organisation here:
"Arrowe Park Hospital’s League of Friends group said it feared for its future if hospital bosses force it to pay rent of up to £80,000 a year.
The charity was founded in 1982 and its shop in the hospital foyer has since raised over £3million for vital medical equipment.
The ECHO understands the shop, which opens seven days a week, has always been allowed to operate rent free."
https://www.liverpoolecho.co.uk/news/liverpool-news/arrowe-park-hospitals-league-friends-13811545