It's a bit odd, but not hard to understand, I 
guess.  After all the recent scams going on in 
cel collecting, I guess people just want to be 
careful.  Getting some references together seems 
like a good way of doing it, without you having 
to do something equally risky, like sending it 
before getting payment.
In any case, you're welcome to use me as a 
reference, too. ^_^