Im maybe going to extremes, but its not about us is it? It is a charity for birds, not a hobby grant. When you donate to WWF they dont go and whack a hut in the rainforest. Public reserves have benefits, of course, but my point is its going a bit too far, veering from its core principle.
Yes, exactly, it's a charity for birds (though the tagline suggests people too).
It's really very difficult to make people give up their money. Giving to charity isn't selfless, it's selfish. People give in order to see a return. I suppose you could see it like buying that warm-fuzzy feeling of having helped, or £60/year for some good karma, or something.
For people to give their money at Rainham, you have to provide something in return. With a nature reserve, that's the visitor experience. A lot of birders don't donate to conservation, so how do you make a "normal" person do it? You provide a comfortable and (relatively) rewarding site visit. Comfortable hides from which (in winter at least) you'll get great views of common waterfowl, a genuinely good visitor centre with decent food, and a flat, dry, wheelchair accessible trail that's not so large that it's intimidating. This is bound to put off a lot of people, people who prefer wilder, less populated places and I can appreciate that, but the public would rather give to see some cute ducklings or the look on their kid's face when... yeah, that kind of thing. Simply put, "but think of the sedge warblers" isn't as good a moneyspinner as "we've got warm hides, colourful ducks and CAKE".
Rainham has changed, hugely, and while it might now be too busy and developed for some people, the net gain since acquisition and management as a reserve is surely huge. I think you have to view all the "small" changes (new hides, a hundred-odd square metres of boardwalk, etc) in this context and weigh them up against the increased "value" of the site since 2000, or whenever they bought it.
The RSPB has protected places for years, without this aggresive marketing strategy. Its become more of a business than a charity, where will it end, charging for carparks, charging a tenner to get in, allowing dogs in?
With the dogs, you're possibly pushing the argument to extremes here, especially given that Rainham has always been very anti-dog. Charged car-parking for non-members however, that seems to me to be a possibility, especially with high visitor numbers and an over-capacity car park. I don't like this either. Increase in general visitor charge is probably inevitable too, though it would go against their inclusive angle.
If that new hide stops even one pair of birds breeding there, was it worth it, when the other hides are 5 mins walk and usually deserted anyway?
For the record, I think the newest hide is slightly redundant. However, as I said higher up this post and, as Rob has pointed out, you should consider these small losses/gains against the huge overall gain of the RSPB acquiring, protecting and then managing the site.