Loading restrictions

There are times I wonder if any of the delivery drivers are actually aware of what those yellow lines at the side of the road mean? You know those single yellow lines on the kerb with the sign that says no loading/unloading between certain hours.

Hello Mr Boots Van parked up at 8:40 slightly offset from a bus-stop on a no loading restricted area; oh silly me it doesn't apply if you get there early. After all what are you supposed to do - cruise around until you can legally park?

Not helped, of course, by the fact I've never seen a warden around at this time. Now call me silly, but if you have time restrictions in an area would it not be an idea to occasionally see that if it's being complied with?