Of course there's alternatives.
You can cut down on non-club costs by eating cheap (fast food, supermarkets, etc). If you go to the beach, take a towel instead of renting the beach chairs.
You can go clubbing in the West End of San Antonio or clubs like Sonmy in Playa d'en Bossa (last year, they were handing out free entrance wristbands on the beach at Playa d'en Bossa). In those cases, you'll spend mostly on just your drinks. The drinks there are also cheaper.
Bora Bora, depending on how it's reincarnated this year, is another good party option. It was a beach club, so free entrance and dancing in view of the ocean, but it's not certain there'll be music outside this year. If not, they may use an attached indoor facility, that had been unused, instead.
If you budget it right, you can still do a couple of big club nights. Just drink beforehand (but don't look drunk at the entrance!) and don't spend once you're inside.