You have a point. But, the same ship at the station can be repaired, refuelled, reloaded, and even upgraded. So why not recharge the shields as well?If there is a way to exploit something then someone will do it.
I can imagine two people fighting evenly matched both have no SCBs left, one loses shields, legs it to an outpost buy a new shield at full, thus bypassing the normal shield regeneration recharge time. Goes and kills the player who is waiting for their shields to come up.
Now that sounds like an exploit to me.
Maybe the answer is to have a spare ship at the station, fully loaded and charged. Same result as an instant repair/recharge. But this is an "exploit" that only those few who have a spare billion credits could afford to use for an anaconda.