It is indeed a courageous act, as long as they had approval for it from a rav and didnt pasken themselves. Putting an indecent ad in any religious area anywhere in the world is highly provocative and senseless act.
With regard to the question of them not seeing the ad in the 1st place, the ???? says ??? ????? ???? ????? ????? ??????
A person first sees and then desires so the pasuk appears to be in the wrong order, it should have first mentioned ??????
and only then ????? . But the answer is that there’s a difference between the initial look/seeing which is accidental, and the subsequent gazing. What a person happens to see initially is not his fault. He must just ensure to look away immediately. The pasuk refers after that first look when the heart is urging him to look again. This is what is meant by ???? ????? ????? ??????. So nobody can question how the ad was noticed initially.