Paul's discussion of meat sacrificed to idols in 1 Corinthians 10:23-33 may seem academic, but this is still a real issue for many people today.
Since eating the sacrificial animal is an inherent part of the sacrifice, don't eat it if the circumstances might lead someone to believe you are participating in a pagan religious ritual. If someone is going to be offended by your service to God, let it be by your actual service, not by your presentation of the Gospel, your offensive and confrontational behavior, or your careless actions when you think nobody is watching.
However, behavior that might appear sinful to someone without all of the facts is perfectly acceptable if that someone can't possibly be around to witness it. Any sin isn't in the behavior itself, but in the stumbling block that it might put in the path of another.