The opinion of the religion on this matter is clear, given that it is forbidden to take part in consuming that which is forbidden in any form. An hadith on the authority of Anas bin Malik (RA) said: The Prophet ﷺ cursed ten people in connection with wine: the wine-presser, the one who has it pressed, the one who drinks it, the one who conveys it, the one to whom it is conveyed, the one who serves it, the one who sells it, the one who benefits from the price paid for it, the one who buys it, and the one for whom it is bought. Narrated by Ibn Majah, and Tirmidhi and the word he said was: Strange, and it was was said by Haafidh and his narration is sound.
The one who serves alcohol to the ones who drink it is a confederate in the sin according to the hadith. This is because either he is content with what they are doing, and those who are content with disobedience will be punished for knowing about it. It can also be said that he is helping them, and the one who helps someone disobey Allah is a part of the sin and a part of the punishment with the one who committed it
The small amount of money that one receives from doing halal, and it only covers the necessities in life and keeps him alive, and he tries his best then this is a salary that Allah will put blessing in, as for beyond what is necessary then it is not permissible to earn it from Haram (what is forbidden)