I've never replaced the caliper mounting bolts on any of the brake jobs I've done. The only reason I can think of is if the bolts are aluminum bolts that are of the stretch bolt type. These are one time use only. Where you see these types of bolts are with head bolts where these bolts secure the head to the engine block.
I'll be doing a brake job on my car soon; at least the rears. I'll examine the bolts when I do the job.
As a side note, I never ever turn/machine rotors. You should never need to. Machining the rotor removes metal from the rotor making the rotor much weaker and more susceptible to warping as the metal removed lowers the heat capacity of the rotor. I only replace rotors when there are signs it needs replacing. Otherwise, I throw on a set of new pads and leave the rotors in place.
Interesting note !
My Rav4 was making strange noises from the front driver side 😨. Hearing this metalic noise when going over bumps - a sound like loose metal. It got worse - like a clicking noise periodically. Got home and took the wheel off and found the top brake caliper bolt missing 😱😱😱. Good thing to have another vehicle to get to the parts store - they had the proper bolt (it did not have any threadlocker on them?). I put some on the new bolt and tightened it back in to spec. and checked the lower bolt as well. I also did a check on the passenger side - still there and "guttenteight" (CSW - reference 🤣 ).
So far no noise at all. Got some extra bolts just in case. Even when going over bumps - no noise.
Whew, close call. No serious damage to the caliper or rotor, but some slight scuffing on the inside of the wheel.
Glad you caught it before something bad happened !