What do you do when your friends go out and purchase the exact same item as you.. and they know you have it already?

Sometimes i'm okay with it if they ask first, and not just show up wearing the exact samething =) but i just think it's annoying when just buy it with out telling you or they'll say "oh i didn't know you have it" when u've already wore it and they've seen it!

I take it as a compliment when a friend buys the same thing, just says we have the same taste in things...