Note: This blog is technically an opinion.
Why did Dan choose seddie? This question has been asked time and again by bitter fans of the opposing ship, and just curious fans in general. The answer is quite simple actually: He never really had much of a choice to make.Dan has been foreshadowing and developing seddie since season one. It's pretty obvious. I don't need to hear him say it to realize that. "They say when a girl constantly rips on a guy"... "Freddie you're just as important to the show as we are..." My sister ,who only ever watched the pilot, saw me watching iOMG and said "They barely just got together?" She knows as well as I do that writers don't generally make two people despise each other as much as Sam and Freddie did just for the purpose of comedy. There is always a deeper meaning behind it. There are many subtle hints during the first season that hint at a possible romantic relationship for Sam and Freddie. If you re-watched the first season, you'd probably see it. Freddie's crush on Carly wasn't just used for comedy either. It was used as a way for Dan to develop seddie. It's understandable if some people didn't pick up the hints in the 1st season, but by iKiss it should've been pretty obvious that Dan has "chosen" his ship.
Then there are those people who are accusing Dan of making seddie happen for the sole purpose of "balancing out the ships." He isn't trying to balance out the ships just to please all the fans. No. In fact, iSYL and iSD were used as stepping stones to further develop seddie. Seddie shippers should have enjoyed those episodes more than creddie fans. These two episodes not only proved that Carly and Freddie wouldn't be able to work together, but also that Sam would be bothered by their romantic relationship.Also,Carly only danced with him after her date turned out to be a douche. She danced with Freddie because he was safe. And then what with iSYL proving that Carly will never be in love with Freddie for who he is. Carly was acting different around Freddie, assuming that them being in a romantic relationship meant that she should find his tech talk "cuky." Sam saved Freddie from heart break. These two episodes were clearly foreshadowing seddie.
There are also those who claim that Dan is doing seddie for the ratings. iCarly is a very popular show. It has been renewed for another season. It doesn't need any sort of "help" where ratings are concerned.
"But Sam and Freddie hate each other." Are we watching the same show here? It's like when Freddie said "I hate you" in iKiss, some people interpreted it as "You're a horrible person who will never find love." And when Sam said "Hate you too" she really meant "Do you not understand that this world would be a better place without you?" :P
Dan has dedicated numerous episodes to further developing the seddie relationship (ex:iwill date freddie, ikiss, ireunite with missy, ithink they kissed, ispeed date, and isyl. That is why seddie is happening. Because writers don't develop a ship as much as Dan did with seddie if they don't have a plan for them.