These stones have local patrons which clean and care for the stone regularly. If this isn't done, the stones do degrade quickly. I understand the objection to

These stones have local patrons which clean and care for the stone regularly. If this isn't done, the stones do degrade quickly. I understand the objection to people stepping on it, but at the same time, where else would you place something to have the same effect? These memorials are so effective exactly because it's a highly unconventional location for them. I've walked past hundreds of Holocaust memorials in my life and none have had the same effect on me as seeing one of these stones with a candle next to it in front of my house on the day of the "Night of Broken Glass"