I often wonder this myself. Why do rich people, who have so much wealth that it is unimaginable to us, not want to pay any taxes? It hampers the economy, makes it less adaptable to contractions, and makes the lives of the vast majority of the population much more difficult. At a macro level, I really don't see any benefits to it. So, here's my best guess.

• Power & control. A poor and uneducated population is much easier to control than a financially stable and educated population. If people are fighting each other for survival and minimal luxuries, then they can't organize to improve their lives as a whole. Add to that being uneducated, they get their "education" via the media and are easily manipulated via propaganda.
• Strength. Similarly, they want to feel strong by manipulating the system to get what they want. By getting the government to do what they want and finding loopholes to reduce their burden, they feel stronger than others. This gives them a sense of strength that they seek, which ultimately means safety for them.
• Greed. They just want the numbers on their bank statements to be higher. Some people are proud of numbers, so the larger the number, the more proud they are. It doesn't matter if the number is relative, so the value doesn't really have any practical impact on their lives. They just want a larger number. I swear, sometimes we should just print fake bank statements wich ridiculous numbers, give them to the wealthy, and congratulate them. That's what they want: to be envied.
• Lack of care. They literally do not care about others. It's not even an issue that fits in their heads. Find someone that is politically right-leaning and ask them what they think about the economic situation in a poor and war torn country. Their response would be indictive of how the wealthy think about us.
• Narrow & short sighted. They can't see the whole picture. They're focused solely on their own relative position on the hierarchy and can't consider how their desires will impact the whole system in the long-term. They can't see that if the lower classes are complacent and uneducated, their products and creativity suffer. Look at Russia where people contribute just enough to get paid and all creativity is to please the elites. This stifles academic and scientific progress while also damaging integrity. People don't contribute to the economy because they have a personal drive. They contribute to please their superiors. This results in a terrible economy full of corruption and lack of ingenuity. The wealthy can't see that because they don't care about it. They just want to feel strong and in control.