I get alot of reaction and comments when I tell people I still play sometime. Everyone "thinks" that neopets is a children's game (in which it is a family game people), but really it is a HUGE metagame with statistics, calculation, etc.
Thankfully I'm surrounded by people that do not care that I play Neopets (the ones that know).
I try to keep it as secret as humanly possible, because honestly I think those are the only two people in my life who wouldn't tease me for it. (Not that I think they'd be mean about it, or that they'd think less of me! I just don't feel like dealing with it.)
Sooooo reactions. The nosy little sister was very sweet about it, especially when I told her not to tell anyone else. She acted like there was nothing out of the ordinary, like I had just confessed that I played Minecraft or LoL. She herself played it when she was like eight, but grew out of it by the time she was eleven.
I went out of my way to tell the boyfriend about it, because he wondered where I would disappear to for an hour or two after coming home. I prefaced it by saying it'd be really embarrassing if anyone ever found out, and please don't laugh at me, blah blah blah.... He was really cute about it, told me, "Ohhh this just means you trust me!" and put on this goofy grin. He'll randomly bring it up to tease me in the middle of private conversations, but it's all in good fun.
Hell, it's much better than smoking weed or drinking as a pastime. I'm a young adult by the way, if that helps with context.
Most people don't say anything really negative. Maybe an eyeroll when they hear I've spent money on neopoints, but then I point out they paid for WOW, so.... haha.
I don't advertise it everywhere, but those that I am closest with know and they don't really care one way or the other.