I am advised by Revenue that purchases made by online shoppers are usually imported either by express couriers or via the postal system. In the case of the express couriers, the carrier make the necessary import declarations and pay duty and VAT, where applicable, to Revenue. In respect of imports via the postal system, the parcels are produced by the postal authorities to Customs and assessed for duty and VAT. The postal authorities pay the amounts assessed to Customs and then recoup this from the importer at the time of delivery of the goods.
I am informed by Revenue that it continuously reviews the allocation of resources to various functions and that it currently satisfied that adequate resources are deployed to perform these functions. However, Revenue is very aware of the increase in online shopping and will continue to monitor trends and respond appropriately to changes in the marketplace.