I also will not bother with the driving licence, unless they automatically do it when I (if I) renew it at 70. As for the discount card most of the offers are on line ones for gift cards, but on the high street there are enough to get 10% off, especially if you are into outdoor pursuits.
I usually try two methods of getting discounts, one is the DDC and the other is the pensioner ploy, so far it has worked in ones that are not part of the DDC side but still gave me a good discount, one said because I asked both those were a double strike and he would add to the cost as a surcharge, he was only joking, wife gets a bit embarrassed when I ask, but likes the discounts when I get them.