I worked in the non profit sector for much of my career. The issue of useful donations is an interesting one. Extensive research on donors, fundraising and charity marketing has shown how important it is to accept all donations, whether useful or not as refusing donations puts off the donor. A couple of examples:
When I was director of an animal shelter and vet clinic, an appeal had been made for newspapers as we used them to line cages and for bedding etc. The response locally was overwhelming. It got to the point that we were being given far more newspaper than we could actually use. We eventually decided to pay for monthly rental on a skip (I think North Americans call them dumpsters) to hold all the newspaper and we would then pay someone to take the surplus to the dump at the end of each month. Why? We worked out that the nominal cost of renting the skip and disposal still left us in great profit because of the good will generated. Every Christmas, all those people who donated paper would arrive with a cheque in their hand. While with the same organisation, we were approached by a gentleman who wanted to bury his dog in our pet cemetery. Unfortunately, we had no room for burials anymore and had built a crematorium so that there would be enough space to accomodate deceased pets. This gentleman was bereft and begged us for help. He offered us a measly donation to assist, but we bent the rules and buried his dog. Turned out he owned a bank. He gave us 100,000pounds towards a rebuild (and yes I know that is shocking when you think about the money available for charities in Belize) in donations and left a great deal of money to the charity in his will.
Community goodwill is the single most important factor when keeping a charity alive. Donors and supporters have to feel needed and appreciated or they drop off like flies. I witnessed one non profit here turn away a donation from a local business because it wasn't up to the standard of donations that they wished to receive. Unfortunately, they have now lost a future relationship with that business, which wanted to become a supporter of the charity and would have donated money and other items had they not felt 'put off' by the organisation.
While it is nice to think that donations are altruistic, they are not. People get a feelgood factor and if they are lucky, a tax deduction. When people try to help a charity and are told 'we don't need that kind of help', they tend to not bother again in future.
Non profit fund raising is all about developing and maintaining relationships with supporters.
Quite frankly, even if this playground was falling apart, as a charity director, I'd be grateful, I'd make my gratitude known and I'd do everything I could to enable the donor.