I'm not sure on the law regarding this issue, particularly in the State of Texas.
But I think that you may be incorrect in classifying the manner in which the debit is presented as an RCC. It may, in form, be the same thing. But that does not necessarily mean that the same set of laws applies. In fact, the statute cited specifically refers to "a bank that transfers or presents a remotely created check . . ." By the plain language of the statute it does not apply to Kroger.
Also, Regulation CC applies to deposited funds availability. It has nothing to do with debits from accounts.
Here in Michigan, most stores that accept checks have a standard sign, posted at the register, informing you that the $25 NSF fee will be automatically deducted from your checking account.
And I've got to concur with Robert's closing implication. I can't even fathom why retail stores still accept paper checks. They inconvenience the other people in line and create an unecessary risk for the store, the cost of which is certainly passed on to consumers at large.
And, given that every checking account comes with a debit card these days, the only reason I can think of for someone to use a paper check at the grocery store is because they don't have any money in their account.
Bottom line, I can't see where Kroger has done anything wrong here. The only problem for the OP seems to be that the collection of the $25 caused further overdrafts.