I'm happy when an instance owner just says how much it costs to run a server, how many people actually manage it and how much time they spend to keep it running. I also like it when they just come out and say "we need this much money to keep things running every month, every year, etc"
Then I just donate and there are more a dozen ways people can send and recieve donations.
I don't mind paying for things and services if the person or people I'm donating to are just honest about what they need and why, especially if it's a service I use often.
No, this is rewarding the implementation of ads and can't be thought of as donating anymore. You are paying to remove ads thus giving them money for having added ads to the site.
What if the ads are optional, they're turned off by default, but if you can't afford to donate but still want to support you can turn them on for yourself?
It all sounds like semantics to me. You could implement donations first and then say OK for all you people who haven't donated we're going to punish you by showing you ads. Bottom line is this shit isn't free. It has to get paid for somehow.