It is rare that you construct a deck that can consistently take advantage of a cheap yet specific hard counter, the only guarenteed advantage of is that you will have spent half the mana your oppenent did
While that might not seem like much, being able to play your titanic Dinos one turn early can mean the difference between winning and losing
A PSA 10 slab adds 38-75% to a Japanese SARs value Pikachu ex SAR jumps from 55,000 raw to ~$516 graded
You can share display boards and binders of your card collection to friends or other players
So much so, in fact, that Diabolic Tutor has made its way into over 110,000 Commander decks
While Ive mostly seen it in Tron strategies, you can run it in other similar decks where you want to access card selection at instant speed