That's because they'er not allowed to in theory. I do signing as part of my job and all round the gypo sites and places they have been to steel signs I replace them with plastic backed plates rather than the aluminium. Not as tough but cheaper to replace.

We even had to light a whole section of dual carriagew way because a gypo on the thieve decided run across it and got knocked over.They'll rob and thieve everything in site but get all moral when one of them gets robbed or injured.

Should brick the entrances to their sites up, bung a lid on and fill the fuckers with bleach