This, simply.
Until i became a parent (where is MY free money people keep saying i get, we get nothing, not even family allowance?) i had no idea how difficult the seemingly simple becomes.
The thought of folding a buggy, on a crowded bus, on my own is borderline impossible. Seriously, it is a royal PITA, despite how pathetic it might sound. And this is before one even considers waking the child. Physically it is like doing a rubiks cube with one hand, and my wife just wouldn't be strong enough to do both. Without kids you just wouldn't appreciate it. Even once folded, there is usually bags & paraphenalia resting on the buggy, which when collapsed will also need to be housed.
The spaces should be reclassified to disabled & parent/child spaces.