You probably voluntarily pay several hundred pounds per year to bring exactly the same crap into your living room via your TV set. Is that acceptable because you volunteered for it? If you don't like commercials, don't watch commercial TV, at home or on an aeroplane.
I agree with Wannabe Flyer. Actually we do not have a TV at home, or electricity, so it is rather novel to sit in an aluminium tube with both. If I remember rightly adverts are a time to get up, go to the loo and make a cup of tea. On a jet this would not work with everyone getting up at the same time and the tea is made for you anyway. If you are about to ditch; sure it would be nice to know and a polite interruption of the film to invite you to put on your water wings is acceptable. However a promotion for the latest Mickey Mouse watch available through on board sales is not.