Nicholas - have a trawl through some of the previous postings on here. Easyjet, along with many low-cost airlines sell mainly non-refundable tickets. Furthermore, while things like Govt tax and airports fees are technically refundable, some airlines impose an admin fee, such that the refund amount you actually get is either nil or so small as to not be worth having.
Easyjet don't really care - they already have your money. If you don't check in, staff will put you down as a "no-show". If you check in either in person or online, but don't turn up at the gate, you will be put you down as "late at gate". Counting boarding cards either issued or collected at the gate is not a particularly onerous task.
If you want to pay an extra fee to change your ticket to a different route or date, by all means do so, but it's most unlikely you will get any meaningful amount of the money back in your bank account.
If your aim in telling Easyjet you won't be flying is purely to be helpful, then, quite simply, you're wasting your time.