Words can be confusing, some exist entirely within the parameters of a single language or culture and others have double meanings with each definition having its own unique usage.
There are also words borne from specific sub-cultures that possess completely different meanings to their original uses. No wonder the English language is considered one of the hardest to learn for non-native speakers!
However, thanks to the evolving nature of language the word 'gamer' is now also classed as a verb in most dictionaries (including the superior Oxford dictionary).
So, as Shakespeare himself might put it; thou art a gamer, if thou doth play!
Your family might be under the illusion that you enjoy the outdoor pursuit of camping and you might not be able to avoid the portable stove and sleeping bag gifts on birthdays and at Christmas.
Just think about that for a second. You might dash someones hopes when they think you are offering them chocolate...how could you?! Just because you consider an in-joke in a game or a secret left in by the programmers or games developers exciting, doesn't mean your non-gaming friend will, they'll just be mildly annoyed that they don't currently have a chocolate egg.
This is one which might not confuse all of your friends, family or colleagues - just the ones who are stuck in the late 80s to early 90s. We understand multiplayer to mean a game mode with the capacity be played by more than one person. Most people know this to be the case, gamers and non-gamers alike - yet an older generation or perhaps your grandmother, will jump to the conclusion that the word concerns a multi-disc CD player or a DVD player that can cater for multiple regions.
Colleague: What do you mean?
Me: You know, co-operative gaming? 2-player...that sort of thing!
Colleague: (laughing) Oh! I thought you meant the Co-operative supermarket or bank!
Me: (feeling silly) Yeah...no, I mean...never mind (shuffles away)