Threatening to kick an 'ungrateful' kid out won't solve the problem
I don't think there's a teen alive who hasn't heard the phrase, "Hey, you don't like it? Then move out!" from aggravated parents. It might be fun to say, but it really doesn't help the situation and can further complicate an already shaky relationship between family members.
Parents often feel unappreciated for all of the sacrifices they make, and feel that teens want all of the priveleges and none of the responsibilities of being an adult. But how many parents hide their financial difficulties from their kids? How is a kid supposed to know that money is tight if parents don't explain the situation? It's bewildering to be screamed at for asking for something in a store if you don't know that the family budget is already in trouble.
Instead of flying off the handle when your kid disagrees with your purchase decisions or with having to do without something, why not sit him or her down and show, on paper, the monthly income versus the monthly obligations? Kids have no awareness of things like mortgages, rent, car insurance, car repair bills, phone bills, or health insurance-- the only expenses they're aware of are grocery bills. Kids always underestimate how much things cost because they aren't the ones doing the bill-paying. If you make them aware of just how limited the monthly income is, a lot of the whining will stop.
For teens, these lessons are vitally important-- they will show that life on their own isn't as great as they might think. To a teen, one's own apartment invokes visions of endless parties and freedom from parental rules. But to sit down and be shown just how much those parties will cost, and the labor involved in doing one's own laundry, housecleaning and cooking will snap most kids out of their fantasies and make them realize that, aside from some inconvenient rules, they really do have a good thing going! Besides, if you toss a kid out on his ear and make him fend for himself without teaching him HOW to fend for himself, guess where he's going to end up once he gets evicted for non-payment of rent? Back at your house! You don't want that, do you? Isn't it worth a little preparation?
Kids can't magically "stand on their own two feet" if you never show them how! Please take the time to do it.