This suicide capsule concept is clearly targeted for people who have made a well thought out decision on their life. Heat-of-the-moment suicides, won't happen with rare specialty devices but common tools/environments/drugs/poisons that are found all over.

It would be a weird assumption to think that a person who carefully plans their suicide in advance, and orders a specialty device for it, hasn't considered options other than suicide. Most likely such a person has tried everything else already.