My small town has four large allotment areas, but there is nevertheless a seven year waiting list. No plots are ever passed on to friends and family, although some are swapped (large plot for small for example - with the council's permission) between plot holders.
One of my children has a large garden and keeps chickens (had ducks but the wily fox found a way in), another is a keen fisherman and has also just got a permit to lay three crab pots. Their brother has a small courtyard garden and manages to grow lots of salads and vegetables - and we have a very large, productive allotment that gives us ample fruit and veg to last the year round. At the moment we're harvesting potatoes, leeks and delicious purple sprouting broccoli.
As you can imagine there is a great deal of bartering that goes on when the family get together, especially in late summer.