You will find that there are snotty people at all Universities.
They have been to private schools, come from families with money, and have incredible 'polish' and self-confidence.
Their world-view is limited and they are totally naïve about the reality of the lives of everybody else.
You get concentrations of people like this at 'top' Unis like Durham - and you notice them because they have no doubt about themselves and their right to be there, and they have loud voices.
Join societies that wont interest them - and surround yourself with friends who are like you, and who get your mindset.
And ignore the Hooray Henrys. You can't defeat them, you can't undermine their absurd self-confidence, so do not waste your emotional energy by trying - or by getting annoyed with them.
Be proud of who you are. Be proud of your journey, and your determination to succeed.
Because wherever you end up in life, you are worth a million of any of them.