I went to a music industry showcase in a club the other night. The first act was British. You didn't have to hear the actual words they spoke to know that. You could pick it up from their body language alone. Anything that was said between the songs came over as if it had just popped into the singer's head and swiftly petered out. It was as if they hoped that if they apologised first then the audience wouldn't be too hard on them if the song didn't go too well. When they looked at each other it was to exchange sheepish glances as if they had woken up to find themselves doing something faintly embarrassing. You wondered how they'd ended up in show business.
The act who came next were a bit more experienced but just as unknown. The difference was they were American. That meant that they meant business. There was nothing apologetic about their body language. They had clearly all had experience of standing up in front of strangers and saying "I'm your server this evening and I'd like to tell you about the specials". They didn't try to banter. Anything they said had been said before. Nobody looked round to work out what was going to happen next. Because they'd all presumably served at least some time doing covers in a bar band, they could probably have whipped out a decent version of "Eye of The Tiger" if things had got really sticky.
I've been watching live rock bands for more than forty years now and it's the one thing that hasn't changed. The Americans haven't come to play. They've come to work.