Hi Rich,
That’s definitely possible and a relatively easy change. First of all though you would need to familiarize yourself with theming The Events Calendar and template overrides in particular – there are links in the Useful Resources widget over on the side to help out here but let me know if you can’t find any information you are looking for.
The idea though would be to copy tickets.php and place it in your theme’s events sub-directory. Then, look out for this code (somewhere around line 68) and change it as directed in the snippet (basically set input_value to 1).
Does that help here?