I see two goals in that paragraph:

Fundraiser for Kamala

Encourage Kamala to make a mastodon account and promote on it over other social media

People have already donated hundreds of millions of dollars to her via more official channels. This is a grassroots fundraiser targeted specifically at mastodon users (and now the fediverse at large because of this post) with the stated incentive of trying to encourage Kamala to use mastodon over other platforms. You could chalk the mastodon but up as secondary but there isn't even a third thing in that paragraph for the mastodon portion to be less important than. Given the amount of press the Harris campaign has already received, it seems like this fundraiser's primary purpose is to promote mastodon via contributing to the campaign and tacitly asking Kamala to sign up.

If mastodon users wanted to donate to the campaign, they have probably been exposed to several other avenues to do that before they would have even seen this. So what's the point of doing a special "fediverse only" fundraiser? Apparently it's to encourage her to create an account. It's pandering and I don't see a point in shilling a super special fediverse fundraiser for a candidate who's already drowning in small donation money when that money could be used to promote the fediverse in a much more meaningful way

I'm not suggesting the organizers of this fundraiser.missappropriate the money. I'm saying that this fundraiser seems pretty pointless and the money would be better spent elsewhere

The complaint is that people care more about Kamala joining mastodon than actually spending money on mastodon.

Your point is irrelevant. No one insisted that people's money should be used for a purpose other than what they consented (please show me where anyone implied that). No one implied that the money isn't paid for kamala Harris with that understanding. Rather, they are complaining about people following such misguided aims.