Right, but I thought to ask it because without double miles, these deals would be half as appealing, if appealing at all, and might not make much sense (or cents). Double miles put the offers in my zone of consideration; no double miles, no interest on my part in a 2.5% fee to pay with credit card rather than by check.

But different strokes for different folks, as neurologists are wont to say. Another FTer did relate how he had bought miles at 2.5 cpm to use for an expensive international ticket and how satisfied he was with the way it worked out. So what does or doesn't work for some, will or won't work for others. The thing is to know what you are getting before you take the plunge, e.g., double miles or not for paying state taxes with a card?; a cap on how many miles can be gained this way?; etc.