website_sale_only_registered/views/website_sale_registered.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
<data>

    <template id="products_price_registered_shop" inherit_id="website_sale.products_item">
        <xpath expr="//div[@class='product_price']" position="attributes">
            <attribute name="t-if">product.product_variant_ids and website.user_id != user_id</attribute>
        </xpath>
    </template>

    <template id="products_price_registered_product" inherit_id="website_sale.product">
        <xpath expr="//div[@class='js_product']" position="attributes">
            <attribute name="t-if">website.user_id != user_id</attribute>
        </xpath>
    </template>

</data>
</openerp>