Disable shipping on checkout page
You can hide it dynamically if no products in the order are
shippable. We are using ubercart 7.x-3.4 and on the Checkout
settings page /admin/store/settings/checkout (Home » Administration
» Store » Configuration » Checkout) there is an checkbox 'Hide
delivery information when carts have no shippable items.' Then, when
you edit each product, the Product information vertical tab contains
a checkbox 'Product is shippable.' 
You can hide it completely on the Checkout settings page /admin/store/settings/checkout (Home » Administration » Store »
Configuration » Checkout) there is a list of the panes available on
the Checkout. If you uncheck 'Delivery information' and 'Delivery method' those panes will never appear.  If you are going to hide the Delivery information pane then the other option on the Checkout settings page 'Use the same address for billing and delivery by default.' would be useful too.