Yes, it's vandalism and really juvenile , but that doesn't mean we won't laugh at it. 

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Source: imgur

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Source: dontknowyou99

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Source: kolkman

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Source: imgur

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Source: somethingawful

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Source: pintrest

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Source: iambored

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Source: somethingawful

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Source: somethingawful

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Source: pintrest

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Source: thechive

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Source: saysit

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awesome sign pranks

Source: imgur

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Source: mandatory