At the risk of being contrarian here (and some might say naive), I'd like to say that (a) I understand the indignation described by several people, but (b) having also been on the receiving end of the same message, I've seized the opportunity on a couple of occasions to discuss the issue with the "offending" waiter / waitress. My conclusion is that in most, but not all, cases, the message has been genuinely intended to be friendly & helpful -- i.e., a waiter / waitress, believing that I would like to leave a tip, seeks to be helpful in volunteering the inherent limitation of doing so when payment is made with a credit card.
The manner in which the message has come to me, moreover, generally has seemed to reflect a cultural difference (i.e., I find that people from France are more "direct" in what they say than Americans are) and, sometimes, a lack of proficiency in English.
In any event, on only a couple of occasions have I experienced a disagreeable engagement when I raised the matter -- both times being in high-end restaurants -- and I simply didn't leave tips. (I've subsequently been back to both places, and I apparently made an impression because they no longer remind me of the tipping issue.)