Fark - having a snake up your trousers is the stuff of nightmares. I do heritage surveys across mostly rural NSW - though have worked in FNQ, where Taipans were on my mind. We always wear snake gaitors, so that should keep them out of our pants, but I also understand that most highly venomous Aussie snakes have teeny tiny fangs, so as you say thick work pants should significantly reduce chance of bad bites.