There is one critical point that is missed by everyone.
The airlines have the ground handling companies by the balls. They pay a set amount of $ per turnaround. For a SAAB it used to be about $125-150. It may be more now but probably not. the airlines treat it as a take it or leave it offer.
Now not all staff are on split shifts. Newbies and the low performers get the rough end of the pineapple. Better performing staff get much longer shifts. Out of a gang of 20 there would be 6-8 on long shifts and the rest come in for the morning and evening smash periods. You simply cannot have 20 people sitting around at mid-day or the company would go broke. Aerocare, Qantas, Virgin, Tiger, Menzies et al do the same thing.
I worked for Aerocare from 2000 to 2007. I had a great time there, learned heaps about the nuts and bolts of ramp ops and made some good coin too at the same time I was a junior instructor. It's very hard work and you do need your wits about you, especially when it's busy and at night.
You would be surprised at some of the qualifications of rampies. CPL's, sparkies, carpenters, mechanics, engineering trades of all types. Anyone who looks down on rampies should do it for a few months.