The same thing happens with buses. People with a brain know it's going to stop because it's a bus and passengers will want to get on and off. So you leave a gap and, when it does indicate and stop, you go past and carry on with your journey. If you're really ****ing thick you drive along 3 feet behind it sucking up diesel fumes. When it stops, you're too close to do anything but wait. You put your indicator on in the hope that someone takes pity and sit there looking gormless.Apparently those recovery trucks are difficult to see, even with all the flashing lights on.
Some time ago I was approaching one with its ramps down at the rear having just collected its passenger. It was a two-lane road although most people wanted lane one as lane two was for turn right ahead. I moved into lane two to overtake said vehicle in plenty of time. The woman behind came to a halt with front wheels on the ramps.