"They used to. Before the creation of the 1 day license you could mix cat 5 with "public" which even further back was called "citizens". These days it's just by category and age bracket, and everyone has a license, either an annual or a 1 day. It's the equivalent of the 1 day."
I've been in races within the last few years where everyone paid the registration fee and you could race if:
-it said Road Cat5 on your annual license,
-you paid for a 1-day license (Cat5) or
-you signed up as 'Citizen'.
The only difference was that if a Citizen placed, they would not get any prize money.
TF