I'm Australian and tend to only use mate in a joking way. The majority of us aren't bogans that talk like this in day to day life but personally I find it fun to put on the voice and play the part some times. No harm in you doing the same where you live.

As anotherponyaccount stated, doing something of quality or kindness. When I said it, it was because this bloke shouted me a beer, so I called him a sick cunt and I got a weird look from him, until I assured it was a compliment

Good reply and all, but if you repeat it i will automatically assume you are a di.... ohhh crap.

Well you are not wrong that this could be a bit attention whoring, like: "Oh yea look at me, LOOK AT ME as I'm doing some random act of kindness by spending some of my money for some strangers, oh yes look at my shirtless chest with the tattoos and stuff". However I would like to think that videos like this will inspire people to be kinder to each other in theri daily lifes hopefully, but suspicions like yours throw that thought out the window.

So what if it's attention whoring? He's drawing attention to a random act of kindness that probably made those construction workers' day. Like you said, the attention will hopefully cause more people to do such acts. There's nothing wrong with feeling good about yourself for making another person happy. That's just spreading more positive feelings.

My issue with attention whoring with acts of kindnesses is that personally they seem disingenuous to me. In my mind I doubt he would have helped the workers if he was alone without the internet, camera or his friend. On the face it doesn't really matter since they are more positives then negatives in this situation but it just bugs me.

I totally understand that. However the point of a kind act is how it affects the person you're being kind to. I don't think the workers would care at all whether the guy was being "genuine" or not, as they're getting a well-deserved cold drink either way.