No, not their income, their output, i.e. expenses.
I'm OK with them spending money to make (i.e. earn) money, or to save money. I'm not OK with them spending money to collect more donations.
For example if you want to hire an expensive but very very good organizer that will save the charity administrative costs greater than it costs to hire the person - no problem.
On the other hand if you want to hire someone who is really good at drumming up support and getting people to donate, that could be a problem, IF they are getting paid a lot. And I don't care that they will bring in more money than it costs to hire them. I'm still not OK with it.
How much is too much? I'd say a few percent - i.e. if it costs more than a few percent to bring in X number of donations, then don't do it. (Or if you do it let people know upfront that XX% of their money is being used to try to get more money.)
That's why I refuse to donate to pretty much any group that calls me. Paying for those calls usually costs around 50% of the money brought in.
There are some cases where the calls are by volunteers, and then it's OK obviously.
Take a raffle for example: some charities will award as prizes 50-80% of the money brought in. Normally I would not be OK with that, except that they are usually upfront about it.
Mass mailing: I don't know how much that costs, but if it costs more than a few percent of the money brought in, don't do it.
A "for-profit charity". That's where someone starts a charity, for the purpose of paying himself a nice salary. Suppose he pays himself 50% of any money brought in.
You might say: well there is still that 50% of the money that does some good, which otherwise would not have happened.
I don't agree.
I think that last case is the example in the article. He says to himself: at least I'm doing some good in the world, so what if I'm making lots. I (and I guess most other people too since he was forced to shut down) don't agree.