Living in Australia I've never tipped anybody in my life as we don't do that here. I can see offering them a bit of cash if they are helping outside the scope of the usual job though so yeah If I had a delivery to be moved a long way I might ask them if they'll help move it for a $20. I'm not really a tight wad but just confused as in our culture it isn't done.

I still don't really understand the culture in the U.S of everyone expecting tips for everything they do, I've been told it's because some jobs have low wages but it also seems decently paid people get tipped for some jobs too? How do you know who to tip, do you tip your accountant? what about for a hair cut? Not sure how people work out who to tip and who not to tip.

see that makes me think the systems even wierder? In other words people aren't really tipping for above average service, they are tipping out of fear that they will get below average service if they don't tip?

When I was younger I worked in a super market and sometimes had to help customers taking their shopping to their car. A handful of times I was offered money for helping (talking small like $5-$10) but we had all been told not to take any money and we could be fired if we did. Man things are different here.