Multiple stars (and flags, maybe?) by a single user

I just noticed that I starred a couple replies, even though I know that I already starred those replies before... I starred a couple replies to a thread I posted, just because people contributed to my conversation. Then, I starred a couple later, because I saw an "empty star" meaning I could star them. Only then I realized I had already starred them... I was the only one who had starred them before, but was able to do so again...

Why was I able to do this? (Maybe the anonymity of the stars?)

Should I give stars whenever I can, even if I already did?

Do some posts get a whole bunch more stars than they normally would because of this? By people who already noticed this, and therefor do it more often?

I'm not too worried about it, but maybe I should be doling out more stars?

(This has probably already been addressed, but I am also aware of the search engine issues on this site, so I didn't even search.)

a reply to: japhrimu

Try refreshing the page after you given that extra star and see if it sticks. It won't.

a reply to: windword

Nice. Checked it. You're right. Got it. Thanks.