But, there are no Commas and spelling in the spoken word...
Actually, that is completely incorrect. Commas specifically represent the short pauses we make when speaking, which in English we're accustomed to doing when saying certain clauses, listing things out, etc. All Punctuation Matters! (bah-dum-DUM)
As to spelling not mattering, I encourage you to submit a poorly-spelled resume to an employer or an poorly-spelled article for publication (even if it's just an opinion piece of the Op-Ed page) and see what response you get.
You may not like it, but people will judge you, your knowledge, and even your trustworthiness by your spelling and grammar. Poor spelling and/or grammar convey a lack of education whether that is the reality or not, and they often lead to the writer not being taken seriously or even dismissed or ignored.
Note, too, I'm really not talking about the occasional spelling or grammar error - everyone makes those from time to time. I'm really referring to the mindset of 'they don't matter as long as people can figure out what I mean', because that is as far from the truth as you can get.
I was going to post a link or two from people who are a lot more scholarly than I on the topic, but there are so MANY really good ones. Just do a search on 'Why spelling and grammar matter' or 'Why spelling and grammar are important' and you'll be buried in articles explaining why they're important and how people react when you ignore them.
Anyway, I really didn't intend to derail the UK Excursion thread; if this is to be continued, it really should be its own thread, either here in the Water Cooler or down in Debates.