We adults get caught in the same trap often too, as doekiller mentioned. Many of us, myself included, deal with both pride (our attitude toward our own nice things) and our envy (our jealousy over the nice things others have).

I'm reminded of the old proverb, not sure of the source:
"Give a man a fish and you feed him for a day. Teach a man to fish and you feed him for a lifetime"

Parents can give generously as much as they want, their right to do so. But there is an open opportunity to use material possessions as a way to teach a teenager and even younger children certain valuable life lessons on money, debt, value, work ethic, responsibility, etc...