To me, a wedding isn't just about you. (Otherwise, why bother inviting anyone?) It's also about acknowledging and honoring all the friends and family who supported you through the years, by including them in a milestone event. It's not an act of narcissistic self-expression: it's a public ceremony and a party, and you need to plan it with not only your own desires, but the needs of others in mind. For my husband and me, this meant we decided on things like a non-destination wedding (some family couldn't travel), an indoor ceremony (elderly relatives in fragile health/using wheelchairs), paying for my own attendants' attire (college girlfriends who were broke and still making the effort to come from out of state to be there), and making centerpieces, favors and flower arrangements ourselves (so we could spend more of the budget on the kinds of foods, desserts, and music we knew our guests would most enjoy). 20 years later, people still tell me it was the most fun wedding they've ever been to.
If this couple felt that it was okay to take the money their parents gave them to feed their guests, and squander it on something so frivolous only for themselves, I don't think it reflects well on their maturity level or judgment. Obviously, they had every right to make that choice. I just think it was a really tacky one.