There's a couple of ways you could approach this:
Add a CSS class to the table to show/hide it depending on whether or not the customer tag exists.
{% assign table1-class = 'table1-hide' %} {% if customer.tags contains 'Trade' %} {% assign table1-class = 'table1-show' %} {% endif %} <table class="{{ table1-class }}"> ...
Only include the table if the customer tag exists.
{% if customer.tags contains 'Trade' %} {% include 'table1-snippet' %} {% endif %}