Couple of answers
First, HTML is a markup language, not a programming language, so it isn't meaningful to ask if it is OO. Second, the reason somone "doing" web pages should know about programming is that any large site eventually involves programming. The content has to be dropped into a framework, and someone has to know how to build that framework. Then add search functionality, feedback, shopping carts ... unless you want to be strictly a graphic designer, you're going to have to know this stuff.
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Microsoft offers them the one thing most business people will pay any price for - the ability to say "we had no choice - everyone's doing it that way." -- [link|http://z.iwethey.org/forums/render/content/show?contentid=38978|Andrew Grygus]