I don't like public proposals when they inconvenience other people.
That's a clear example as the day will have been overshadowed by the impromptu proposal. The people who then get their certificates afterwards won't be the focus as people will be talking about the proposal.
Worst one was when I went ice skating in London with friends and we were discreetly told by someone who worked there that everyone had to get off the ice as someone wanted to propose. Absolutely not on my timeslot. If someone wants to propose in public they can pay to rent the area out because there was no way I was shortening my time slot so somebody I'd never met before could propose 🙄. Apparently several people refused to on the grounds of already paying, and time slots couldn't be extended due to the next group of people being due
Just screams entitled and 'look at how elaborate I am".