I agree with Jeremy. It would be better for you to convince them, than have another web publisher do so, later on. Ideally, you want people to come back to you. Yes, it's their choice, at the end of the day, though they might appreciate being informed of their options.
One more thing. At the risk of sounding dreadfully sententious (I hate pedants) but I feel it would be a terrible shame to perfect your syntax and web standards, only to let yourself down on the spelling, punctuation and grammar, which is so essential to publishing.
That's meant to be helpful, by the way. Sorry. I hope you are not dyslexic; in which case, I'd understand, though I suspect you think text-speak is acceptable, outside of an environment which charges by the word.