Reason #1: you have position on the flop Reason #2: you have already invested a blindee Reason #3: against you will rarely Reason #4: you'll extend your range and improve skille
I'm assuming you mean when it folds to the SB and they raise (we would be out of position against anyone else).
Yes, you will gain experience by playing more
hands but I would suggest loosening up on the button and in late position instead of out of the blinds (this way you are in position).
The fact that you posted a blind doesn't really affect much, that money belongs to the pot and while you will be getting a better price than those who are not in the blinds, you will generally be paying for this with a lack of position against all but the SB.
Good luck at the tables!