mmace is right. We realize that we are not the norm, so we are not offended by things that other people just take for granted. We do not drink coffee, black tea, or alcohol, and we do not smoke. If offered, I would simply say "no thank-you", but I would expect you to simply go on doing things the way you usually did. I would not drink coffee, but I wouldn't be offended if you drank it in front of me. When we go to office parties and things like that, dh and I are used to expecting that others will drink.
LDS people usually do not swear or take the Lord's name in vain, so we always appreciate it when others refrain from those things around us.
Other than that, I can't think of anything else right off hand.