Why there is graffiti all over Santiago Chile

Santiago, Región Metropolitana de Santiago, Chile
Why there is graffiti all over Santiago Chile
I noticed that there is graffiti all over Santiago. Is this a cultural aspect that is widely accepted by Chileans? As a tourist from the U.S., I find it unappealing and associate it with negative connotations like crime, poverty, drugs, etc. How do Chileans perceive this graffiti? Is it seen as a form of expression or something more problematic?
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