When they start getting fined , maybe then they will learn to tie them down. Or if the boats comes off !  

 Afraid I am going to plead guilty to that.  Only time I have ever tied the boat down is when doing a long trip so might have to think about getting a strap out and doing it, especially after the one I saw in Exmouth where the bloke tipped his old mans 23 foot ali? boat on its side and dragged it 80 metres up the road before stopping, took about an hour to get it back on the trailer completely blocking the road. The young bloke got carted off by the coppers so no insurance.

 This unfortunately is quite a common sight along with people not even hooking up the safety chain to the bow and relying soley on the winch to hold the boat on the trailer.

Seriously how hard is it to throw a strap over the boat after you have retrived it.

Not securing your boat correctly not only poses a danger to your pride and joy it has the potental to injure/kill other road users as well.

Never did I do now

 I've always thought as you get older, its better to strap it on than see your most loved vessel get pounded down the road.

 Never used to when I had a trailerboat but started when I took a borrowed tinnie up to Cape Peron.

I do it now even for my 10 min trip to woodies, dont need any extra grief.

 Can someone post the regs on this?

I seem to recall that securing loads on trailers required a secondary restraint and interpreted that as 1st could be winch, 2nd could be the chained to post. 

I secure my boat with straps when travelling long distances as recommended on DoT website "When trailing for any distance, fit straps to hold the rear of the boat onto the trailer as well. These stop the boat squirming and bouncing on the rollers"

Have always tied any boat to the trailer, although back in the day it was with rope. These days when fishing local  it's a quick and simple routine at the ramp with my centre console.  Winch to the post, safety chain on to get off the ramp. Then, once parked for derigging,i ts just a quick walk to the transom to put on a couple of short transom ratchet straps. Fitting and tensioning the two transom straps takes less than 30 seconds a side and couldn't be simpler. For country trips I add  a 50mm web strap side to side across the hull just behind the console. My trailer came standard with steel loops at the rear and midway along the sides, so the straps just hook on to those. Once you have a routine like this it is  just a habit, takes no time and gives peace of mind.

 I've always tied my boats down across the back, from one side to the other with a ratchet strap.  It only takes a minute or so and worth the peace of mind. I had my tow hitch handle, the bit you use to lift the trailer onto the ball that locks the pin break the other day. Luckily for me it actually broke at home when I went to move the trailer. I did fall on my back hitting my head on cement but not seriously hurt. Imagine if it had broken while driving down the Freeway though. At least with the boat strapped there might be a slightly better chance of it surviving, Maybe.