DFW data - I have brought a mixed case of wine into DFW. They asked if I had receipts for the wine, and I said no. They asked if all the bottles were the same and I said no. They asked me if it was for personal consumption and I said yes. They waved me through. I got the impression they were supposed to charge me a tax based on the cost of the wine, but realized it would be a nightmare to calculate it.
For hard liquor, I have brought more than my limit (1 liter, but in practice 2 x 750 mL is generally waved through) and had to pay $1 or $2 per bottle. For some reason they did not take cash and I had to charge $4 to a credit card.
I have been told by CBP that the limit in Texas is 1 liter, regardless of alcohol content so a liter of scotch is OK but technically 3 x 12oz bottles of beer is dutiable. <shrug>