I wasn't going to comment on the economics but, having read some of the other posts, maybe I can make a couple of useful comments. You probably know about the dual nature of the economy in WA - basically it's mining and everything else. The problem many many employers - including hospitality folks - have is that they can't get decent staff who'll hang around in the face of a 'trickle up' effect to the resources sector. In practice, this means that the unemployment rate, especially around Perth, is basically zero for anyone who wants to work and has a few functional neurons.
I'm not suggesting that commonly available work is glamorous but, with a bit of forward planning, you could do OK. For example, taking a short barista and hospitality course before you leave the UK could be worthwhile. The ability to make a coffee that didn't require a couple more passes through the horse would instantly distinguish you from most Perth operators
. An example at the less desirable, but maybe more lucrative, end of the scale came my way the other day in the form of a Scots working holiday maker in a crew repairing my storm damaged fence. Hard work, no doubt, but it is there.
It's undoubtedly more restricted in the regional centres but don't get put off by raw statistics - a lot of people in the sample group are effectively unemployable (just like the UK) and the whole point of being young and ambitious is to believe that the stats don't apply to you! For example, I recall an interesting conversation with the LAME at Bunbury about his attempts to employ a reliable junior gofer. Despite a theoretically large pool, it proved just about impossible.
So by all means do some homework and preparation but no need to believe you can't do it if you want it badly enough.