A key part of event marketing is ensuring that you have worthwhile pairs of ears in the audience. Of course, you can't stop people coming to your event if you don't think they're good enough, but you can target your promotional messaging to ensure that the right kind of people find out about your event.
Buyer personas already better target content marketing for blogs, promotional content and your overall marketing strategy, however they can be used to take it a step further.
If you amend your buyer personas to become event-specific personas you can avoid inviting people who fall outside of your target customer base. Don't waste money and resource on extra marketing and event costs because there are individuals wasting your time by attending. Those who aren't interested in your products or services are even less likely to attend full stop, despite registering their interest. Ultimately, wasting places that may be valuable to you.