I've seen such gate drive circuits used when driving relatively large IGBTs over long leads (like over a foot of twisted pair). That's generally because of the problem you're referring to, with parasitic turn on of devices (which can happen to both low and high side switches). But if your driver circuit has a low impedance connection to the gate and source of each device, then I doubt it is really necessary, and the pnp won't make the turn on any faster (unless you're working with very large IGBTs or FETs).