Hi Sarah,
Quantity items must be purchased as a part of a registration process. However, you could certainly set up an event in Cvent with the sole purpose of selling merchandise/swag quantity items. (Ex: It could be a very simple process where people would have to enter in their first name, last name and email address and choose from the available quantity items to purchase and submit payment.)
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Julia Plymack
Senior Client Success Manager
Cvent
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