M_J, cost is, of course, one of the reasons for posing the question. That and the lack of any de-icing facilities.
I do appreciate that a can of de-icer costs an arm and a legs, but the cost of not deicing the aircraft properly can be both arms, both legs and all the interconnected parts.
As a can of aerosol of de-icer costs 70p, I have no hesitation about using the entire can to get all the surfaces clean, coupled with the use of a rubber scraper to remove any slush/water.
What I want to know is is there any reason not to use automotive de-icer, such as paint damage, deteriotion of rubber seal, crazing of perspex, etc etc.
If there isn't a good reason, this poses the question, 'Why don't flying Clubs use it?