Yep; you are missing something, but as with all CAA docs the wording is terrible.
You can fly during the day without the navigation lights and red strobe, subject to MEL requirements. You can't depart if your flight time will take you past the onset of official night (30 mins after sunset)
Most light aircraft have a placard in the cockpit which says something like "Turn off the wing strobes on the apron in the vicinity of other aircraft, at night or when IMC." The strobes on big aircraft are a long way from the cockpit/cabin and are well shielded from cockpit/cabin windows. On something like a PA28 or any Cessna they are much closer and at night or IMC can cause a horrible distraction.
In fact I believe, but can't check right now that there is no requirement under any set of laws for wingtip strobes, just the ordinary red/white/green nav lights and red strobe.