I hate to see that stuff and, yes, it’s everywhere.
Not sure it should be small, just because he’s the only guy to get caught.
However, if he was physically abused, it was wrong and he’s due his recourse.
I suspect in many communities it is technically a violation and “vandalism” to attach posters in many areas. Just like it is technically wrong in many areas for political signs to be put on the roadway, because it is public property. You can put it on YOUR OWN property, but not technically the property along the roadway.
Of course, when someone loses a dog and puts up a sign, no one is seriously concerned about that or going to suddenly send in SWAT.......but when it comes to politics...
As usual, the problem is often selective enforcement.