This is how I hide stock quantities - I don't want my competitors knowing how much inventory I keep.
1) Look&Feel>>Webmaster mode
2) Edit Template: /default/en/product/details/stock/body.tpl
Comment out the quantity tag using {** *} here is the template:
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{* vim: set ts=2 sw=2 sts=2 et: *}
{**
* Product stock
*
* @author Qualiteam software Ltd <info@x-cart.com>
* @copyright Copyright (c) 2011-2015 Qualiteam software Ltd <info@x-cart.com>. All rights reserved
* @license
http://www.x-cart.com/license-agreement.html X-Cart 5 License Agreement
* @link
http://www.x-cart.com/
*}
<div class="product-stock {getFingerprint()}">
{if:isInStock()}
<span class="stock-level product-in-stock">
<span class="in-stock-label">{t(#In stock#)}</span>
{**
<span class="product-items-available">({t(#X items available#,_ARRAY_(#count#^getAvailableAmount()))} )</span>
*}
</span>
{else:}
{if:isOutOfStock()}
<span class="stock-level product-out-of-stock">{getOutOfStockMessage()}</span>
{end:}
{end:}
</div>