It was a wonderful night. On September 23rd, 1993, one scene in television history changed the boundaries of surreal sound effects for ever. On "Seinfeld," George did a surreal laugh in which the post-production crew basically took his yell and exagerrated the yell so that it could "be heard" across the entire city. It was a cliche born that, used in many Nickelodeon comedies and many surreal comedy shows and movies. I think the shows on Nick are so similar in that they are minstrelsy, only it's even more bizarre. I think they owe it.
Sitcoms started in the early 50's, not with Seinfeld. It's a style like Movies are a style, therefore, if you want to run down that rabbit hole, we could say any movie ever was influenced by "Citizen Kane".
Seinfeld is simply the crown achievement in a long history of a single genre of film: the sitcom. Nickoloden picks Sitcoms up because they are dirt cheap, easy to write for, and easy, easy, easy to crank out, which they do, if you haven't noticed. As soon as one show gets "worn out", they adopt a new gimmick and start a new show.
This is not a new tactic. They did the same thing in the 50s.