People shouldn't discount other peoples experiences for the simple fact that, You are not them... Your experiences are not necessarily the same as others. I have personally used and seen numerous others use hi-lift jacks on the trail for anything from lifting a tire off the ground to re-seat a bead to using the jack handle as a sleeve to trail fix a broken tie rod. Safety is the key.
It is stupid to discount a tools functionality based on the possibility it can be used inaccurately. You CAN get injured by ANY tool if you're not using it correctly or using it beyond the limits that it is designed for. Hi-lift jacks are as safe as the person maintaining and using them.
There is a tool for everything,, (ok maybe not everything) and there are tools designed to be useful over a wide variety of tasks. The hi-lift can be used for multiple tasks so long as you use it the way in which it was designed to be used with the proper attachments, and safety practices.