You all seem to have disappeared up some dark place. believing the sun shines out of there. What you have to remember is that you're developing for other people, not just for developers like your coterie of friends.
Jo, I'm with you in your first response "What I tend to do is try to talk them out of whatever thing they want to do that isn’t good for the visitors".
There're more than enough developers, clearly, prepared to do whatever "the customer" wants. And there're more than enough customers for me to make a comfortable living while I'm maintaining standards. I'm writing for a particular market segment. Let's face it, if I'm developing for those customers who can't be bothered listening to me, they're in the "amateur" sector anyway. For the big, corporate, clients -- clients most interested in maximising returns on money invested, those most prepared to learn what research has shown works most effectively -- I won't be using a "builder" program, like BSS, Mobirise, whatever, anyway. There's a reason such programs are best for quick and dirty jobs