All day events not recognized

Hello! I use Google Calendar and make frequent use of All Day checkmark when I'm blocking my calendar (vs. creating an event that begins at 9 and ends at 5). It appears that Scheduler doesn't recognize these all day events as the time is being offered as available in my schedule. 

Has anyone else seen this issue? Is there a workaround (aside from going  back to making a 9-5 appointment)? Thanks for your insights.