My parents never really expected me to work either. I've never really worked a 'real' job in my life, except for two summer .com internships. However, I worked for myself. In high school I earned a decent amount of money through website advertising and in college I earned a large amount of money through eBay - it was about a 3 hour a week job that earned massive amounts of money that no 'normal' easily available student job could compare to.
Since I kind of know where you're coming from, I'm not going to say 'you're a stupid spoiled little brat and deserve to die' like most people here are going to tell you. If your parents are willing to give you money, then that's great. People are going to attack you like none other, but I'm sure you were expecting that. Perhaps your family situation is similar to mine - my parents would give me money whenever I need it and in turn I would without hesitation give my parents money. I see no shame or problem in that. If you're ungrateful, then that would be wrong. It seems that some people here don't understand that some families work differently than their disfunctional family.
So, just ask your parents for the money. $120 is nothing. It's an almost insigificant amount of money. If they've given you money before, they should give you this. Maybe they'll say no since it's kind of a frivolous item.