aldi do their own version of graze snacks (tubs and packets) which have gone down well with my DH. In a similar vein, high protein snacks and jerky also got a good response
toiletries, especially if slighter posher than he would get himself. Things he secretly enjoys but would never buy himself as it's not 'manly' - face mask, bath bomb, chapstick, decent hand cream
razor pit for 'sharpening' (more like cleaning) razor blades. Saves money too as it extends the life of each cartridge.
gift cards - cinema / coffee shop / steam in particular get a good response
flavoured coffee / coffee syrup
ultralightweight gloves with magic finger (so he doesn't have to take them off to use his phone)
alcohol miniatures and beer
'posher' air freshener for the car than the tree shaped things he buys himself
power pack - anker do some great portable ones
slipper socks with grippy soles
on the sweet front, a wilkos tub of pic n mix was a big hit. Morrisons often has a good range of American sweets. Posh chocolate always a hit
scratch card or lottery ticket