Re: Price difference - a high security lock costs $100 or more, while commercial grade builder's hardware may cost $10 or less.
However, like Daniel hints at, a product that claims 'bump proof' or 'pick proof' is similar to a camera that claims '0.000001 Lux'.
It's a nonsense claim that needs to be explained more deeply than simple marketing, because not every product claiming to hedge against bump risk solves it in the same way. This, coupled with the fact there are legions of 'sport lockpickers' that would rather do nothing else that post Youtube demos of 'bumping' marketed bump-proof locks.
Features of 'bump resistant' locks include additional design features like shaped top pins, locking sidebars, and trap pins. See image below for the least expensive feature: shaped top pins -
These features are part of 'high security locks' like Medeco or Primus, but those products don't claim to be 'bump proof' on factory literature. Rather, they make the 'high security' claim that contrasts them against other locks and partially explain why they cost hundreds rather than tens of dollars.
Anti-bumping design features do not eliminate the bumping risk, but just confound it or make it very difficult. Like most security equipment, adding time to defeat a 'security layer' is invaluable to hardening it against exploit, but may never eliminate the risk.