Well, maybe not... Perhaps (just perhaps) they will accumulate then into a single donation "from" that IP, or maybe allow multiple clicks if they don't get to their target number of visits. I doubt that they will allow loads of clicks from one address though - that's one reason that I stopped at four.
It's still good anyway - just visit, click, 25¢ goes to help others. It clearly helps to raise brand awareness, hence is a form of advertising, and is likely entirely tax-deductible, but I certainly can't complain.
Ed: BRiT isn't the only one who can read...
Only one click per visitor per web session will be eligible for a donation.