Logical and fair, but you’re assuming a zero-sum game with a predetermined amount of money in the pool, when it’s certain that better campaigns can and do bring in money that wasn’t necessarily going to be donated to any cause at all.
A) If they bring in more money than was originally in the “pool”, it’s not a net loss. In fact, it may leave extra money in the pool for the other organizations.
B) If they are a cause I prefer, I’d rather a smaller percentage go to a cause I prefer over a larger amount going to a cause I don’t and by proxy
C) If they are a cause that I feel is more worthy, I’m happy to have my money used to propel money from elsewhere into my favored cause.
Something else not mentioned -
A well run organization won’t necessarily have a fixed % going towards overhead. They might spend $50-100k to launch a campaign along with a small commission for the site running it, the more money they raise the lower the overhead is as a percentage. So would I rather give to a great cause that already spent $100k, got the attention of 100k people and raised $5mm or is it better to give to a campaign that spent 1k, got the attention of 5k people and raised $100k?
Going a little deeper into it - every campaign has a certain amount of people that would give to it without any special marketing necessary. In the case of the larger org, assuming they may have gotten 1mm while keeping marketing costs at a minimum, but now they can spend 100k to raise 4m from people who wouldn’t have given that tzedakah otherwise? Why not? It’s a no brainer, and it’s not a zero sum game. Meanwhile the low overhead org will raise 100k but not a dollar from people that aren’t running to give.
If I’m giving anyways, I’d perhaps prefer give it to the org that knows how to generate 5x my donation out of thin air to make my dollar go further.
TLDR, a well run org spends money to raise huge sums mostly from people that wouldn’t have given otherwise