Are bounding exercises really essential to a sprinters program? Can one still attain good results with just sprints, weights and plyometric movements such as reactive box jumps, shock and depth jumps, when used accordingly of course?
Anyone out there 
There are many ways to skin a cat and it can be done without bounding. Reasons to avoid bounding, such as shin stress hard surface etc, should probably preclude depth jumps as well IMO.
I don’t think bounding/hopping per se is bad, but it takes a fair degree of skill and a high strength-to-body weight to execute correctly and many people go straight to bounding on the track to try to elicit greater stride length and quicker contact times from the outset. Starting off on a grass incline or wooden stadium benches allows the athlete to develop both of these with out exposure to the extreme impact of a flat surface.
I agree with Charlie that plyo’s aren’t essential, but I also know that some sprinters benefit from them greatly and suffer with out them in their programme.