Just to add if you were to willing eat meat in front a Hindu knowing full well that this would offend him, this would be
Makruh so while not wrong, it would better to avoid it,
Yes the advert is disliked from both the christian and Muslim point of view and it would be better to avoid such actions when possible. Which I think is the problem we have with the OP, while we could encouraged our fellow Muslims and Christians not to act in a way that would offend someone, how do we encouraged non-Muslims and non-Christians to do the same. I suppose the best could do is voice the opinion that we dislike such actions and have faith/hope the offending person would stop and reconsider his/her actions,
In truth when the tables are turned and the Muslim is the one offending the non-Muslim, we as Muslims could only but encourage that Muslim that is his his/her actions are Makruh i.e. disliked and encourage him to reconsider.