B2B marketing?????

I started thinking about B2B market and was wondering how much of it is really out there and how much do we as consumers actually see? I know that B2B is a huge industry compared to B2C but how much advertising is really involved. I realized we actually see quite a bit on a daily basis and just don't realize it really. One that I recall that I found interesting was movie theaters advertising for businesses to run their ads before shows. Usually you dont see them advertising this you just see the ads. Another thing you see alot is financial commercials and IT systems for businesses. These industries are becoming increasingly outsourced and commercialized. How many IBM, CISCO and CITI commercials do you see. These are basically all aimed at atrracting businesses. I guess its one of those things we get used to seeing and it gets lost with all the other advertising we are exposed to every single day.