Robot, the short answer is yes.

Just search eBay, rat rod, and see the garbage some people cobble together.

Compound the isse with different standards of safety.

What is safe? 15 mph.crash test? 5 mph?
How many of you run your rod into a wall to check the work?
Use OEM standards as benchmark?
How many cars have been deliberately manufactured with known safety issues, all for the bottom line?
How many rods are being built deliberately with decades - old brake and suspension technology, is that safe? Or even using antique parts, how often does an old spring get magnafluxed before it is returned to the street after fifty years of sitting in a scrap pile?

Hey, if I struck a nerve, It's ok. My point is to make you think, and if it raised your dander, then your'e thinking, mission accomplished.

The short answer is yes, if the parts are out there, then ignorance and avarice will see them used.