Foggers can be very beneficial but I think it depends on a number of factors. I am not an expert on this topic by any stretch of the imagination, but I have read that a specific type of fogger/humidifier is needed in order to provide benefit to chameleons, and some may even be harmful to chameleons (largely due to their propensity to accumulate bacteria). A well planted bioactive enclosure that is misted thoroughly before lights out should provide similar benefit (without the extra cost, work and risks) through water evaporation and transpiration through plants.
Additionally, almost all advice, tips, guidelines should be filtered and interpreted with respect to your specific setup and environment. Some guidelines which are relevant for certain species may not apply to others. Appropriate misting times vary greatly between screen and glass enclosures. 5/6% UVB tubes are most often recommended for veiled/panther chameleons but for many, 10/12% may be more ideal. etc.
This is why, if you have the time and patience, it's better try and understand the specific reasons behind why certain recommendations are given.