An asshole who preorders/buys an item as soon as it's available and resells it at a higher price point than the item originally sold for. Usually is fat, lazy, or has no actual job.
Johnny: I went to Gamestop to get the new Destiny game and they were out of stock and I had to buy it from a scalper.
David: What an asshole, preying upon innocent people wanting to buy something that they find interesting.
Someone who purchases large quantities of goods (usuallytickets) early with the sole intention of re-selling them at a higher price at a later date (closer to the event).
Seedy looking guys outside stadiums avoiding police and trying to sell tickets to baseball/football games which are about to start.