Collimation is like fine tuning a car's engine - you can get away without it, but the performance is crappy. And to be honest, I don't always tune my Newtonians either, but I wouldn't let it go on for more than one session without a quick check.
It can also be a bit tricky to figure out how to actually align the optics, which is all that collimation is, just with a fancy word. The process for me is now routine, takes no more than 5 minutes tops, and the rewards are staggering.
As Malcom says, some reflectors are more tolerant of this misalignment than others. Also if the scope is a solid tube it is less prone to big changes than a truss/collapsable tube. But all benefit from a tweek.
You don't need fancy gear to do it either. Have a look at this link on how to collimate your reflector
. It goes through the process without the use of fancy gear, and explains well the role of both the secondary and primary mirrors in the alignment process.
If you are unsure on how to do it, I'd be happy to show you as I see you are in Sydney too. It isn't difficult, and having someone show you takes out a lot of the guess work. Drop me a PM is you are interested.