ha ha! looks like you had even worse experiences than i did!
the worst was in romania on holiday when i was protestant.
i tried hard to keep a note of which churches had which rules, and thought we were going to a baptist church,
where only married women had to cover their heads (they hardly bother these days, this was about 20 years ago).
so i did not take a scarf, as i had only just got engaged and so did not need to cover.
when i got there, i found out it was an evangelical church, and was annoyed with my fiance for not checking.
i sat through the service bare headed, so even though i joined in most of the hymns and was fervent in my prayers,
i still got passed some leaflets on how to become a Christian by the lady behind afterwards.
i said thank you and was about to explain that i was already a Christian, but she had already left.
obviously my bare head had pointed out my need for salvation clearly enough, and no discussion was required!