It is to be stressed that what is unlawful for a Muslim is still unlawful for him/her wherever he/she goes. Unlawful behaviors remain unlawful whether in a Muslim or a non-Muslim country. Muslim scholars agree that stealing from non-Muslims is forbidden. By having citizenship, a residence permit or a visa of a non-Muslim country, a Muslim enters into a peaceful agreement with non-Muslims, and he must respect the agreements and never betray them. This is because respecting agreements and treaties and honesty are among the basic characteristics of a Muslim.
The eminent Muslim scholar, Sheikh Muhammad Al-Hanooti, member of the North American Fiqh Council, states: A priority in a Muslim’s life is to please Allah and to demonstrate the best manners of a human being. The teachings of Islam are not effective if not practiced by good Muslims. How would a Muslim make da`wah (calling to Islam) to a non-Muslim if he/she is showing him that they have double standards? All those doings you mentioned are sinful and shameful.
What is haram (unlawful) is haram for everybody, wherever they are. Categorizing certain areas to be “Dar al-Harb” or “Dar al-Islam” does not fit the realistic understanding of Islam, especially when you live in the Western countries. Al-Mawardi says, ‘Wherever you practice your deen (religion), that is Dar al-Islam.’
Sheikh M. S. Al-Munajjid, a prominent Saudi Muslim lecturer and author, states: No one is unaware of the fact that stealing is a major sin, for which Allah has enjoined the punishment of having the hand cut off. The Shari`ah makes no distinction between the wealth of a male and the wealth of a female, or between the wealth of a minor and the wealth of an adult, or between the wealth of a Muslim and the wealth of a non-Muslim. The only exception made by the Shari`ah is the wealth of non-Muslims who are waging war against the Muslims.
The Muslim should be a good example of trustworthiness, honoring agreements and good character. When Muslims have had such characteristics, this has been the cause of many non-Muslims entering Islam, because they saw the beauties of Islam and the good character of its people.
The Muslim who regards the non-Muslims’ wealth as permissible, whether he is in a Muslim country or in a non-Muslim country, is doing the non-Muslims a great favor and helping them to distort the image of Islam and Muslims; he is thereby helping those who are launching attacks against Islam.
When a Muslim enters a non-Muslim country, it is as if he is entering into a peaceful agreement with them – which is the visa which is given to him to enable him to enter their country – so if he takes their wealth unlawfully, then he is breaking that agreement, in addition to being a thief.
The wealth that he steals from them is haram. It was narrated that al-Mughirah ibn Shu`bah kept company with some people during the jahiliyyah (pre-Islamic period). He killed them and took their wealth, then he came and entered Islam. The Prophet (peace and blessings be upon him) said: “As for your Islam, I accept it, and as for the wealth, I have nothing to do with it.” According to the version of Abu Dawud, “As for your Islam, we accept it, and as for the wealth it is obtained through treachery, and we have no need of it.” (Reported by Al-Bukhari and Abu Dawud)
Al-Hafiz Ibn Hajar said: The phrase “and as for the wealth, I have nothing to do with it” means, I will not touch it because it was obtained through treachery. What we learn from this is that it is not permissible to take the wealth of non-Muslims by treachery when they have trusted you and granted you safety, because when people accompany one another (when traveling), they do so on the basis of mutual trust, and that trust should not be betrayed, whether the other person is a Muslim or a non-Muslim. The wealth of non-Muslims is only permissible in the case of combat and war. (Fath al-Bari, vol. 5, p. 341)
Ash-Shafa`i (may Allah have mercy on him) said: When a Muslim enters Dar al-Harb on peaceful terms, and finds himself in a position to take something of their wealth, it is not permissible for him to take it, whether it is a little or a lot, because if he is safe from them, they should be safe from him, and because it is not permissible for him to take anything from them when they have given him safety except what it is permissible for him to take from the wealth of the Muslims and ahl adh-dhimmah (non-Muslims living under the protection of the Muslim state). (Al-Umm, vol. 4, p. 284)
As-Sarkhasi, the famous Hanafi scholar, said: It is not right for a Muslim who is on peaceful terms with them to betray them, because betrayal is haram. The Prophet (peace and blessings be upon him) is reported to have said: “Every betrayer will have a banner by his backside on the Day of Resurrection, by which his betrayal will be known.” If he betrays them and steals their wealth, and brings it to the Muslim lands, it is not right for a Muslim to buy from him if he knows about that, because he has obtained it in an evil manner, and buying from him is encouraging him in that, which it is not right for the Muslim to do. (Al-Mabsut, vol. 10, p. 96)