Sister Glo, you should read up on heads of state in the Islamic Caliphate, namely Abu Bakr (R), Umar (R), Uthman (R), and Ali (R), the four rightly guided rulers of the muslim state after Prophet Muhammad (SAW). they didn't live luxurious lives. they didn't eat or dress like the monarchy while the rest of the public were dying. In fact, they had to be told by others to eat right because of how little they were eating! Abu Bakr (R) got a small daily allowance while he was ruler. this allowance wasn't enough to pay for dessert so his wife tried to save some money each day so they could buy some sweets. after a few days, she told him of the money she had saved each day. Abu Bakr (R) took that money and returned it to the state treasury known as the bait-ul-mal, and told the treasurer to reduce his daily allowance by that amount.
once the bait-ul-mal had given each person a certain amount of cloth. Umar (R), the second Caliph, had also gotten a peice of cloth , but he was was really tall, so his piece was not enough for his clothes. a man saw him wearing full length clothes that couldn't have been made from one peice of cloth and so enquired how Umar had gotten more cloth than his right. Umar (R) smiled and said that since his son was present, it would be better for him to answer the question. Umar (R)'s son said that he had given his own cloth to his father.
Once Umar (R) was told that he should eat better. he said that he couldn't until every person in his kingdom was eating the way he did. once he said, my case is like that of some people going on an expedition. their belongings are collected and given into the custody of the leader. what would happen if the leader took all their belongings for himself?
Umar (R) used to walk around in the streets at night making sure that no one was in trouble. once when he heard some children crying because they had no food, he went and brought a sack of flour on his back from the baitul-mal to the children's home, and then cooked it himself for them , and didn't leave until the children were fed and happy.
so all this shows that the money collected by the government is not for the leader to use as he wishes. the ruler will answer to God about how he used that money and also about the condition of his subjects. if anyone in the kingdom is hungry or homeless, while the ruler is living luxurious, the ruler will be asked about it and punished by Allah on the Day of Judgment.
The rightly guided caliphs were aware of this so they lived such modest lives.