Is this how the service is supposed to behave? The current FAQ specifically says "notifications", not "messages", which implies to me that only notifications (i.e. automatically-generated ones, not messages sent in response to a command) should count towards the quota, not responses to the "help" or "menu" messages, nor responses to the "Read" command. (All of these deduct credits right now.)
If the service is indeed supposed to take SMS credits for responses to sent-in commands, the FAQ should be updated to reflect that. I'd suggest:
"Receiving Messages: Depending on your account level, you receive a certain amount of free messages from TxtLJ per month, which expire at the end of each month:"
then at the end of that section:
"Note that any message from TxtLJ will deduct a message credit. This includes messages sent to you in response to commands."
And maybe the entire FAQ should be reworded to replace the word "notification" with "message"?