I hear you, which is why it's important to wrap rationality in forms that make it look like Mars Bars. Here is one example of how I do this. As you can see, this piece was shared over 1K times, so pretty popular (the baseline average for that site is around 100 shares).
Yeah, that's one way, and I suppose there is an important battle to be fought at the margin - some people can are on the boundry between celery and mars bar, and you may be able to help them.
The Less Wrong meetup in Columbus, OH is very oriented toward popularizing rationality for a broad audience (in fact, Intentional Insights sprang from this LW meetup). We've found that doing in-person presentations for secular groups is an excellent way of attracting new people to rationality, and have been doing that for a couple of years now, through a group called "Columbus Rationality" as part of the local branch of the American Humanist Association. Here's a blog post I just published about this topic.
Most importantly for anyone who is curious with experimenting doing something like this, we at Intentional Insights have put together a “Rationality” group starter package, which includes two blog posts describing “Rationality” events, three videos, a facilitator’s guide, an introduction guide, and a feedback sheet. We've been working on this starter package for about 9 months, and finally it's in a shape that we think it's ready for use. Hope this is helpful for any LWs who want to do something similar with a secular group where you live. You can also get in touch with us at info@intentionalinsights.org to get connected to current participants in “Columbus Rationality” who can give you tips on setting up such a group in your own locale.