Texas has a large population of illegal immigrants, who often work "off the books" ... i.e. would not pay income taxes.
Texas has a relatively high sales/VAT and property taxes to make up for the lack of an income tax. The added benefit of that it is much more difficult to avoid sales and property taxes. So both legal and illegal residents end up contributing to the state taxes.
The nice thing about property and sales tax is that you can control your expenses. Live in a smaller house, pay less in property taxes. Spend less, save more, then pay less in sales taxes. It's a system that really incentivizes saving.