You don't have to pay for a drinks licence but you do have to pay for booze and no, sorry, not this time. It's a simple matter for people to buy it themselves and realistically the club could fork out on a bunch of crates and there'd still only be two or three sneakies per person. One way or another, the club will not be spending so much money that you can get drunk for free. So if you want to go boozing, you may as well buy your own.
Also, I vaguely recall some fuss from the fresher of the year night last year about how you have to have your drinks reception in this one particular room before moving on to another room for your presentation (or vice versa, or something weird like that). so it's messy whatever way it goes.