Who knows, it may even give you an opportunity to tell them why you don't do what everyone else does. Another small and everyday example. It doesn't matter, everyone travels at 10 kilometres per hour above the limit. God's people are not everyone else. Do not confuse being legalistic with being legal.
Legalism is bad, but legality is good.
Do not use your freedom in Christ as a cover up for evil, says Peter. Christ and the early church were not anti-authority. We are called to be submissive people. Paul says in Romans 13 the authorities that exist have been established by God to restrain and punish wrongdoing. Peter says the same thing here, and adds that we must also submit to the authority of others over us such as masters, in verses 18 to 20.