1) Why would you be ashamed of your love for a fellow Gaian?
Because enough Gaians have horror stories about how one gift led to begging, which in turn led to being stalked, harassed, etc, and, in the most tragic (and, ironically, grandiose) of endings, something like hacking occurs...
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2) Why would you want a nice deed or kind gesture to go unnoticed?
If not for the reason above, I'd say because some do not want others to feel obligated to them... As in, some random person gifts you an expensive item... if you don't know who they are, you won't be inclined to feel like you have to repay them or something, whereas if you know who they are, you might start acting, how would say, different around them
cat_rolleyes
3) Are you afraid you'd look like an internet stalker of some kind?
Anonymity has served ***** quite well for years... Although, I'm skeptical of this kind of logic, since I see equating being an Internet stalker with that of gifting someone on Gaia as, more or less, a sign of immaturity, which many still, surprisingly, bear on Gaia
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4) Sometimes, a nice deed or gesture can have ulterior motives, especially from creepy guy/gal who can't be bothered to tell you their name.
Like the above, I'm equally skeptical of this...
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5) You just got gifted a fairly valuable item from anonymous. Aren't you just a little skeptical?
Skeptical? No, not really... Grateful? Surprised? Shocked? Ja, I very much am...