There is one message that is important to put across to you... the event attendees:
TICKETS ARE CASH ONLY!!!
Anything else you can use interac or credit cards on. Take for example these recent arrivals:
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Shearwater - Rook (Matador)
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Spiritualized - Songs in A & E (Spaceman)
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Accidental - There Were Wolves (Thrill Jockey)
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Aethenor - Bedtimes Black Cloudmasses (Southern Lord)
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Boris - Smile (Southern Lord)
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Bowerbirds - Hymns to a Dark Horse (Dead Oceans)
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Eric Chenaux - Sloppy Ground (Constellation)
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Mount Eerie - Black Wooden Ceiling (k)
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The National - A Skin, A Night DVD+EP (ADA)
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Photon Band - Back Down to Earth (Emperyean)
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Silver Jews - Lookout Mountain (Drag City)
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Venetian Snares - Detrimentalist (Planet Mu)
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Vetiver - Thing of the Past (Gnomonsong)
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War on Drugs - Wagonwheel Blues (Secretly Canadian)
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Wooden Shjips - Vol. 1 (Holy Mountain)