The best thing you could do is find the ugliest most beat up mailbox and put that up. More than likely they would leave that one alone. It is the nice ones they like to hit. Tells you something about our society.
I know some guys that would stop and pick up a couple six packs of beer for the trip home after work. What to do with the empties? Throw them at mailboxes obviously. That went on for a few weeks, hit some, missed some. Then one time a piece of glass bounced back and hit a guy right under the eye. I think that cured their mischievousness.
I lived on a busy wide state highway and got my mailbox creamed from a snowplow a couple times. In Wisconsin that is par for the course. Then one day I took the bottom half of a 35 gallon barrel, stuck a 6x6 post in and put a mailbox on top. The concrete was sitting on top of the ground except for an inch to make it level. Everyone steered clear of that mailbox.
Then I got a letter from the post office and said that wouldn't work because it is to dangerous. What if someone drove off the road and hit my post before they hit a tree, oh goodness. But, I am easy to please so I rolled the whole thing 5' farther from the road and put a 2x8 on top long enough to get the box closer to the road. I didn't have any problems in 15 years after that, but it still looked wicked.
About 10 years ago a guy was going to put a trailer house down the street but the mailbox was on the corner and the driver couldn't make the turn without the trailer swinging and hitting it. I noticed two guys out there starting to disassemble the box and pole. I went out and showed that all they had to do was lay it over, then I did it. When they were done I just stood it up again.