Manglesphoto Loc: 70 miles south of St.Louis

Actually the screws are called Torx-tamper proof, you can buy a cheap set of bits for less than $15
I had a plate stolen and a sticker many years ago, now days the stickers are designed to tear apart when some one tries to remove them.
The thief looks for the easy score, plates with these screws would make them move on to something easier.

Fayle Loc: Seward, Alaska and Rionegro, Colombia

A dab of 5 minute epoxy on each screw head prevents any tool from working.

sr71 Loc: In Col. Juan Seguin Land

Crazy Glue not really! Just a little more torque on the screw will brake it loose, red loctite a lot of difference.

DirtFarmer Loc: Escaped from the NYC area, back to MA

Never had a plate stolen and never had a plate installed with any of the fancy "security" hardware. When I needed to change a plate I got my set of hex drivers since all my plates were attached with screws with a hex head.

I had an old truck. The bumper rusted to the point where it would not pass inspection. The inspection guy said "just put something there. Anything at all". So I got an oak log. Used the chainsaw to carve out a flat space in the middle for the license plate. Had to use a large drill to install the plate lighting. Attached the plate with lag bolts.

I thought the log looked much better since I left the bark on. At about 8" in diameter, it was stronger than the original bumper.

If you think you need security hardware for your plate, you might just consider metric hardware.

Another fastener I have not seen a driver for is a screw that has what looks like a phillips drive, but the teeth in the driver do not form a cross. They are offset so there's a little jog in the middle. They are used on aircraft. In grad school we built a piece of equipment to be installed on a research aircraft. They required that sort of hardware so we had to redesign our equipment to use it. There would be a right and and a left hand version.

Rough drawing

Manglesphoto Loc: 70 miles south of St.Louis

What everyone is missing is the mind set of the thief.
With the advent of Aluminum lic. plates they no longer need a screw driver, they can rip the plates off and reinstall with washers over the torn out holes. If they can't they will just steal another.

Manglesphoto Loc: 70 miles south of St.Louis

Hell I can get that screw out without a screw driver
Tools needed: a hammer and a small punch!!!

Alafoto Loc: Montgomery, AL

"They will need a jack hammer to remove the screws!!!" So will you when a new tag is issued.

DirtFarmer Loc: Escaped from the NYC area, back to MA

So the real thing to do is look at your plates regularly so you can report a theft in a timely manner.

EdJ0307 Loc: out west someplace

I bought a used car from on a car auction several years ago (still have it). It had one locking lug nut on each wheel which I wasn't aware of until I had a flat tire and had to call AAA to change the tire. And of course, since it was an auction car it didn't have the key to remove the lug nut. Had to have the car flatbedded (is that a word?) to the tire shop to have the lug nut removed. Had them remove all four of them.
It also had a locking gas cap without the key, of course. But that was easy to remove thanks to a YouTube video. Now I wonder what the point of the locking gas cap is if it is that easy to remove without the key.

Manglesphoto Loc: 70 miles south of St.Louis

To keep honest people honest as with any lock.

jimvanells Loc: Augusta, GA

It really doesn't matter how sophisticated the head of the bolt is. In two weeks that new design will be at Harbor Freight for 99 cents.

Smokin' Joe

Had a rear plate stolen from motorhome parked in my yard, Paradise, CA . Pretty brazen. Reported it about 2 years ago.