Question involving Sesame Street episodes

[mariolover]

I have a question that I don't know the answer to if any of you guys can answer this. Why have no TV episodes of Sesame Street ever been commercially released unaltered on VHS and only a select few on DVD through the Old School box sets and the TV Episode Fun Packs? I feel like they should've released every classic episode of Sesame Street unaltered commercially on VHS as I am a huge VHS geek and some episodes are super hard to come by.