According to what Sean Parker wrote, it's somewhat inaccurate to call it a $4.5 million wedding:

  "I will say, against my better instinct to tell you, that we
   spent roughly $4.5 million on prepping the site and big part of
   that was restoring the forest floor (I should say, covering the
   forest floor with plants) since it had been paved over in black
   asphalt or cleared by bulldozers before we ever laid eyes on the
   campground."

Taking what he wrote at face value, perhaps $3M or more of that remains behind as an improvement to the forest itself. If he spent that $4.5M renovating a dilapidated church and then had a potluck wedding where he spent nothing, would that still be a $4.5M wedding given that all the value accrues to the church itself?