I've just taken a quick trip to Noosa for an elopement and I flew the same airline I always fly.
The incentives laid out by that group's frequent flyer program mean that I'm far more likely to fly with them - even if it costs more, and it often does.
Price is but one part of your large marketing story.
What other incentives exist for people to book you as their celebrant, other than the fact you're the cheapest - or that you're available?
Just to be clear, I don't think a frequent marriages program is the answer 😉.