Why do manufacturers use nonstandard bolt head types? Is it just to make it more difficult to the DIY-er to get away from visiting a dealership? It was already too much work to dig down to the cylinder heads on my Tacoma, just to find out that the head bolts are not regular hex heads. They look like
triple square but I just learned they are actually not and are
double hex instead. Why all of this seemingly unnecessary confusion ? Is there a practical reason to use something other than standard that most people have tools for?