Why is raising better than calling?

I think that folding here is horrible due to the amount of outs we have for improvment by the turn. I think calling here is good and then we can see what happens on the turn.

We are in a position that if we improve (we have a high chance to be ahead of LAG?) we can raise and charge the whole field 2BB. This may get us a free showdown against LAG and we will have around 8-9 outs on the turn if we don't already hold the best hand.

True