Why doesn't GTA 4 have a m garage for many cars like in past GTA's?

Seriously, I really enjoyed being able to pull to the docks or my big garage in GTA3 and calling up any vehicle I wanted. I believe there was a similar feature in GTA:VC. I really liked being able to have any car in the game at my disposal, but in GTA4 the reserved parking even seems to be unreliable sometimes.