One might imagine having a service lie to, for example, make it look more busy (so as to attract more users) and/or to detect cheating. Is this a reasonable thing to do? See for example how the ESP game lies: http://www.cs.cmu.edu/~biglou/ESP.pdf. In particular, take a look at the sections on Pre-Recorded Game Play and Cheating.

If you think that it would be morally wrong to lie in this way, would it be better if the service told you that it may lie at times to enhance the user experience?