Hidding username should not be used to make people curious but it is more about security purpose.
using the hide feature also protects you from spam message and spam tips .big players often hid themselves because they are being targeted by beggars . some are just plain stingy and they do not want someone to see them ( i.e thier friends ) because thier friends might beg on them . ive done that too on the past but i realized that it still up to me if i will give some tips or not , its not thier money anyway but im trying to give too sometimes if ever i win huge .
You are correct it is nice for more security. But they should be excluded from promotions.
Honestly there is an etiquette of casinos as well that hidden usernames try to get a pass on and I understand. You guys keep saying that "beggars" ask for money, but normally 5 years ago or even more, when someone won a big bet they shared a bit of it with the chat, as a way of celebration obviously, they didn't need to, they weren't forced to, it was a cultural thing that started in just-dice website first where people who wagered over 100 dollars and won over 100 dollars were giving away pennies, not even a dollar, but it was like a lucky charm to them and it got stuck.
Nowadays everyone expects gamblers to do the same because it is a cultural thing, you don't have to and by all means you shouldn't if you don't want to, but also do know why they would want something like that or at least why they would expect it.