We went up yesterday, and there wasn't a soul there, all afternoon. The lanes and roads to and from were busier than I've ever seen them with people 'out for a walk'. The site was busy at the weekend, when we will try to avoid it, because that's only fair (as we can go in the week). Although I am concerned we may end up not being allowed up at all (in Spain and Italy you are only allowed to go 100m or 200m away from your house now. They are stopping and checking, and can tell as you must carry an identity card and have a police check each time you move house, and are issued with a notice when you are stopped, so they can tell if you are stopped again. I believe people are still allowed to work as normal, though)
I would much prefer to visit the plot than a shop. Although of course visits will be more frequent this time of year, they involve significantly fewer people, outside, so the infection risk is vastly reduced, and visiting now will help ease any shortages later. It will also involve contact with fewer higher risk people, and give anyone who is higher risk more autonomy to shield.