Doodledog
Firsts, like any other grades, are not in the gift of individual lecturers. There are checks and balances to prevent people taking it upon themselves to decide who gets what, and people don’t get to set standards of their own.
This applies within modules where there are different staff marking assignments, across different modules on courses and between different degrees. There is internal moderation at assignment levels, and External Examiners moderate between universities to ensure fairness there, too. If there is grade inflation (and I would agree that there has been) it is a sector-wide phenomenon.
I have had colleagues who liked to think that they could withhold marks, as in their heads their standards were somehow superior to others’, but they had to get off their high horses and accept that the system wouldn’t let them.
When it comes to regional ways of speaking, the chances are that non-standard English would be marked down in an essay, but much like on here, (where, for example, the use of ‘uni’ instead of ‘university’ is tolerated), in general conversation it doesn’t matter.
There will always be those in any walk of life who cling to anything that gives them a perceived advantage, and mocking others for syntax errors, and assuming that this denotes a lack of intelligence is a cheap way of doing so. One of the advantages of going to university is usually that students meet and mix with people from outside their ‘bubbles’ and learn to respect differences, but there are always those who are too set in their ways to benefit.
I rather agree with you, even though I've made a couple of jokes. Considering that my grammar and syntax cannot pass unchallenged, I'm being a tad hypocritical.
Some days ago my partner, who is Swedish (therefore English is not his native language), noticed that the word "disgusting" was not infrequently written as "discusting" and wondered if in fact it was an alternative spelling. This lead to a conversation about spelling / grammar, etc.
The English vocabulary is huge - one of the biggest - and certainly larger than his native Swedish, also Norwegian. When we both lived in Norway, I noticed that when a native Norwegian couldn't find a word in their native language to describe something, they would often use an English word. He said this is quite common in both Norway and Sweden - where English is the 'second' language.
He's quite fluent in English, both spoken and written and thinks it's a lovely language (he is an Anglophile anyway), and does not tolerate well those who mangle it. He is - in Swedish, pedantisk!
We both agreed that there is a difference between people who try to articulate, but sometimes get the spelling and grammar wrong (which I certainly do sometimes) and those who are just too lazy to bother or care.
I never pick on any individual personally for their spelling or grammar (people in glass houses, etc), but I make an exception when (usually on Facebook) a random person is insulting me because of my POV and does so in a diatribe full of spelling mistakes and / or poor grammar; particularly if that person has told me - as one particular woman frequently did - that I'm a deluded 'lefty' who should get a education because I think stupid. 
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