Interesting. I think the county isn't getting much in value in return for the datacenter, though the numbers stated in the headline can easily confuse a headline-reader. The $3.3b in tax breaks is on the $30+b of GPU purchases for that location which would normally encounter sales tax and so on. The coverage for that tax break is a state law, it seems[0]:
> The company is expected to take advantage of a new Louisiana incentive program, established by Act 730, that offers qualifying projects a state and local sales and use tax rebate on the purchase or lease of data center equipment. Meta is also expected to participate in the state’s Quality Jobs program.
So it is entirely normal that the county officials wouldn't know or really get a say, and the county is the one that's missing out on sales tax. The Louisiana governor isn't hiding the fact that they're going to give them tax breaks, though. It's right in their announcement.