Placing "Do people win on scratch cards?" starts with the family it belongs to. Every casino floor carries a few games that are neither cards dealt to a hand nor a wheel with a ball in it. Keno, bingo and scratch cards all work by matching numbers or symbols already decided somewhere else, and casino war sits beside them as the shortest game in the building. They share a shape: the player commits first, and the result arrives in a single step.
Keno asks for a handful of numbers from a field of eighty. Twenty are drawn, and the payout depends on how many of the picks appear among them and on how many were picked in the first place. That second half surprises people: matching four of five is a different prize from matching four of eight, and each spot count has its own column on the pay table. The table is the game, and two venues running the same draw can pay quite differently.
A scratch card is a draw that already happened. The whole print run is decided before any card is sold, so the prizes are a fixed set distributed through the batch rather than a chance calculated at the moment of play. This is why a card cannot be luckier at one time of day than another, and why the remaining prize table for a run is a more useful thing to look at than the odds printed on the back.
A caller draws numbers one at a time, and each player marks them on a printed card until a winning pattern completes.
The table of prizes still remaining in a run shows what is actually left to win, which says more than the overall odds on the back.
When both cards match in rank, the player chooses to surrender half the stake or raise and go to war; the house draws most of its margin from ties.
The two games use fields of different sizes and count different patterns as wins, which is why the rules sheet for each matters more than it seems.
Matching four of five picks is a different prize from matching four of eight, so each spot count gets its own column, and venues can pay quite differently.