I'm with the OP on this one - I always take the half - second key press to enter Hanger out of politeness, and am already in the station message boards, or selling stuff, before my ship has been put in the hanger. You CAN hit the button to put your bird in the hanger, then immediately start selling, delivering, buying or outfitting stuff as your ship is put away. Why not? And, yes, once I was so hacked off at someone sitting on the pad, I opened fire on him (and got a nice big fine).
Two options
1. As the station you land at automatically pings your engines when you land, why doesn't it also scoot your pad away into the hanger automatically (unless you push the PLEASE DON'T button within 5 seconds). This could kick in at busy times so automatically storing you and your bird to let others come and go.
2. Allow ships on open-to-space landing platforms to be damaged if they are still on the pad, and are shot up. This SHOULD encourage people to store the ship in the hangers, so as not to get shot up when simply trading. Obviously, should be possible within larger enclosed stations, but internal station security should unleash on the aggressor with unholy fury if they do. Would make the game more interesting.