I advocate for "Truth in Advertising". Of course, if the switch is more appealing than the bait (yeah... right!)...
Posting fake photos is wrong. Recent studies indicate that 9 out of 10 fish are resentful of the bait and switch approach to marketing.
Nowadays, when photo verification is so easy (i.e., TinEye)... it boggles the mind how anyone with a modicum of sophistication would fail to see the detriment of such practices. Marketing is a tough game... but I really appreciate the honesty of a not too touched up pic; then again, I guess I'm just old school on the subject.

ame