I know many people don't care about spelling, and there are good reasons many people can't spell well. This post is for people who do care, it's not to cast judgement on people who can't.
It's an interesting phenomenon where these bastardised words start appearing here and there in social media, and within a matter of weeks they take off and it seems like everyone is using them. Aswell is very new on the scene, I doubt anyone was writing it a couple of years ago.
Link to prove I'm not making it up:
dictionary.cambridge.org/grammar/british-grammar/as-well-as