Is it permissible to evade taxes and customs by reducing the price of goods, paying a bribe, or being dishonest, especially if the government does not provide services to citizens? And is it more fitting to collect Zakat instead of taxes and customs?

As for knowing how the government spends the money, this question should be directed to the specialists.

Regarding the second question, the Muslim ruler must send out collectors to gather zakat, in fulfillment of Allah's saying: "Take, [O, Muhammad], from their wealth a charity by which you purify them and cause them increase" (At-Tawbah: 103), and because the Prophet, peace and blessings be upon him, and his successors used to do that. The recipients of zakat are specified as eight categories mentioned in Allah's saying: "Zakat expenditures are only for the poor and for the needy and for those employed to collect [zakat] and for bringing hearts together [for Islam] and for freeing captives [or slaves] and for those in debt and for the cause of Allah and for the [stranded] traveler - an obligation [imposed] by Allah. And Allah is Knowing and Wise." (At-Tawbah: 60).

It is not permissible to evade taxes or customs duties unless there is absolute certainty or a strong presumption that these taxes have not met the conditions for their collection.