Bob’s an adrenalin junkie, but he’s also a lily-livered coward.
Unlike other adrenalin junkies who seek out extreme sports like skydiving and rock climbing and scuba diving, he’s barely able to make it out of bed without going all freako and diving below the covers again.
So, to get his adrenalin rush, he has it shipped to him.
Then, when he’s finally able to get out of bed and sign for the package, he scurries back to his bedroom and opens the box.
And then, staring at the contents, he dives back under the covers.
(Bob’s afraid of needles, too.)