I have to ask why we make ourselves crazy trying to come up with a low cost solution for someone who "Wants the look" but doesn't want to pay for it? As Dianne pointed out, even with free branches there's a lot of work involved with this type of thing. And shouldn't the time spent scrambling through brush piles count for $$$? I think this is why people don't respect what florists do or feel like it's not worth monetary value - all that brain power, creativity, brush scrambling is worth something!
And don't get me wrong, I'm all about budget friendly solutions, but I see nothing wrong in saying "I'm sorry, but that's not in your price range" and offer an alternative. If crystal trees on every table is not affordable, what's wrong with suggesting a pair for the ceremony and something else for the tables.
I'm going through the same thing right now with a corporate client "who really wants to use" me, but won't tell me their budget. As a non-profit, I'm sure the budget is no budget but their wish list is specific and HUGE, so how much time and effort and creativity do I want to put into the proposal? It's all a fantasy at the moment.
Price things whatever way you need to in order to make money. Don't discount your energy, brain power, creativity. Nothing is "free". If other people can make money being cheaper, learn how they do it, or find your own way.