The answer is yes, Web guru Jeffrey Zeldman says in a new interview. Read this if you still don't think following Web standards is essential. Read it anyway if you're already enlightened. A snippet:
Most of us are still using techniques that date from the mid 90s. We slice and dice images, stick them in tables, write scripts for different browsers, use browser detection to find out which user agents are being served, and so on. We're writing markup with no basis in structure, because when we started writing h1 and h2, Netscape put big white space under our headlines, ruining our pretty layouts. So we learned to write nonstructural stuff, such as div class="subhead2". We couldn't use HTML out of the box, so we learned stuff that made our sites look OK. But we robbed them of any underlying structure.