|MadSci Network: Chemistry|
I would agree with you that most products merely tend to mask the odors present with perfume. Some products claim they actually destroy the odor. I don't really know how they would want to do it. I guess you could try to oxidize some of the organic species, yet doing so without potentially endangering the health of the person using the spray could be difficult. There are ways to remove odors from an air mass, but they would have to involve more complicated chemical or physical activities than what's contained inside a can. I can imagine the use of filters, activated charcoal denuders, washing flasks and the likes, as they are known from cleaning processes in chemical engineering.
I would personally discourage the use of such sprays as I consider them useless and think that they smell bad. This is my personal opinion and I have no scientific proof for it. The EPA has a booklet covering the whole issue of indoor pollution. I think they have a very healthy attitude addressing potential indoor pollution concerns. Here is the link: http://www.epa.gov/iaq/pub s/insidest.html
Try the links in the MadSci Library for more information on Chemistry.