The Pasuk in the Torah that says לפני עור לא תתן מכשול, not to put a stumbling block before a blind person, has interesting connotations.
The most famous one is that we are not to give bad advice to someone who doesn’t know better. He is blind in a sense and relies on us for direction.
Another aspect of לפני עור, applies to our dealings with non-Jews. We are not to present obstacles in their obligation to observe the Seven Noachide Laws.
An example would be the following: Gentiles are not allowed to worship idols as one of the seven laws. Therefore, it would be forbidden to sell jewelry to a non-Jew that has a cross, a symbol of עבודה זרה. It would especially apply if a store owner would entice with a very low price.
It would be a good idea for those profiting from tourists to be careful not to violate לפני עור, in their dealings with non-Jews.