Every culture has had materialism, and has had objects that are coveted. Older cultures have found ways to channel that in useful, or at least relatively harmless, directions. In the South Pacific, groups of islands have a custom of passing shell necklaces from island to island, adding a bit to them each step, according to set and complex rules. So everyone gets something to brag about, but it's a harmless use of a bit of excess energy and ... shells. The Tlingit etc tribes of the Pacific Northwest use to accumilate food and goods, and then share them all and destroy much of the goods (such as ceremonial copper shields) in their "potlatch" parties.
It seems like materialism is instinctual in humans but there are various ways to act on that instinct. Our own culture has had characters like Andrew Carnagie, who said the most fun about having great wealth was in giving it away, and did so.
I don't see any problem with your "coveting" a $30 bike that you'll probably get into tip-top condition and then eventually give away or sell for probably less than you actually have in it. That's a pretty far cry from the head honcho at Nike making tons of money on the backs of slave labor.