I spent a year picking fruit'n'veg around Aus back in 90's .... I was having a break from my career, imo something everyone should do at least once to get an idea of a different lifestyle, There are a wide variety of people who do this work. Just like in all different occupational groups. Quite a few young women talked of sexual predation but not just from opportunist employers.
There weren't many Aussies but most of those that were eschewed the dole and worked their butts off making a good income. Depending on the farm work, there were a good few grey nomads, older people who worked their own patch solo (these were the hardest workers) and some who I considered sexual predators........ there were also a lot of interesting muso's who'd travelled Europe doing the same thing, working in the orchards and acres in the day and busking/playing coffee shops at night..... one amazing guy had jammed with some of the best in US, Euro and UK for years. Never took a cent of Govt largesse.
of the backpackers, most were European from my experience with many who really wanted to make a few bob, enjoy the socialisation and parties and frequent sex, and many who were couples, often in teams, who were more interested in travelling and seeing the country but who worked hard to raise the readies for further travel (it was these with whom I teamed up). I also did a spot of busking/jamming and coffee shops.
Stereotyping is meaningless. All it results in is creating problems for yourself and for those whom you stereotype. There is a rich variety of people in my career occupation too from those who hide in the library, those who socialise instead of doing their work, some who work diligently and some who are zealots.
Lets not get stuck in the mud of judging a whole sector with your prejudices.
