I find it hard to believe that, unless you live somewhere very remote, that people cannot manage to shop in (from Love 2 Shop website):
'Argos, Boots, Matalan, River Island, TK Maxx, Peacocks, New Look, Schuh, Heron Foods, HMV, Go Outdoors, Waterstones, H Samuel, WH Smith, Pizza Express, The Perfume Shop, Halfords, Iceland, Wilko, Home Sense, Foot Locker, iFLY, Ernest Jones, The Works, American Golf and The Food Warehouse'
Surely you'd just buy food from Heron or Iceland/Food Warehouse, or cleaning products/toiletries etc from Wilko rather than let the money go to waste? Then use the money freed up to buy an actual gift from anywhere?
But I would caution against giving vouchers for individual shops/restaurant chains, because if they go bust, you've lost the money. A lot of the chain restaurants have been propped up for years by cheap debt and it's going to be a rocky time ahead for the likes of Pizza Express facing the perfect storm of increased interest rates, increased cost of utilities/NMW/ingredients in a climate when people are having to cut back on eating out due to reduced disposable incomes.
I've given my teenage nephews and nieces £20 in a card, along with a box of nice biscuits for the family. They're all already mentally spending the money over the Christmas holidays that they'll receive from me and other relatives.