No, there is nothing dishonest in comparing gods to Russel's Teapot or an invisible pink unicorn. On that, we agree. However, to do so is, in my opinion, to relegate gods to the realm of the absurd. Again, there's nothing dishonest about doing that either. I also don't have an issue with an atheist not believing in any given god for whatever reason they choose.
To relegate gods to the realm of the absurd and then say "I just lack belief" is where my issue lies. At that point, the only purpose I can see for claiming lack of belief is one of convenience. As far as I'm concerned, once you've considered gods equal to an invisible pink unicorn, claiming lack of belief is just as meaningless as my lack of belief in the purple space hippo.