I think it also depends on what kind of a collection you have. Do you have just a corn snake?
Then maybe you just wash your hands with some sanitizer and you're good to go.
Do you have 1000s of dollars worth of various reptiles?
Then you'd be darn right you aught to take every precaution necessary.
Here's the thing, yes vet bills for one snake are best avoided by taking precautions. However, am I going to tell someone new who's only supply line is the local pet store that their snakes are all going to die if they decide to buy bedding there? Or that they need to wear a face mask and rubber gloves to go shopping? No that's an easy way of convincing new people that reptiles are disease ridden and difficult to keep.
This is one of those advice given is based on level of keeper for me.
When I was younger I kept 14 different species of reptile and amphibians at a point, from a variety of sources, breeders, pet store, wild caught. I only ever quarantined maybe 2 or 3 of them. (of course this was before the whole extinction fungus that is infecting amphibians going on now). Most things that did end up dying died mostly because of husbandry mistakes made by a 12 year old.
For me the biggest and most important step to preventing disease in a collection is the selection of the animal. Properly examining the animal and the animals around it. Now in the internet age this becomes almost impossible. But its just my experience.