We have seen some truly awful anchoring techniques. The sports fishing boat that drove into Port Man, dropped the anchor at speed and kept going till it stuck. They had a helluva job getting it up! The motorboat that put down about 7m of chain in 5m of water. The ones who go right on top of an anchor buoy.
This chappie drove in right next to us just after we'd moved Roaring Girl (being slightly worried about the depth where we were). He dropped his hook not on top of ours but not far away. We wouldn't have like his position, because any swing put him close to some little fishing boats on mooring buoys, but that's his choice.
Then he puts out a stern anchor! So we asked him if he planned to stay the night. Oh yes. We said, we're a bit worried because we have 30m of chain out (in 8m of water), and we could swing on top of you.
Monsieur Golliwog (the name of his boat) shouted back that of course we were the type who objected to anyone within 20m of us. No, we said; only because of your stern anchor. In the end, we told him it was his problem if anything happened, and took some pictures in an ostentatious fashion.
Thankfully, some hours later, the wind has died and he has taken his stern anchor in.
People do anchor very close here; there is no tide, but in some ways that makes it worse as boats veer unpredictably in wind shifts. French boats keep their fenders ready at all times - it's not just those marina arrivals, it's the anchorages too!