Why is rummy is considered a skill game and not gambling?

[Snehals]

Why is rummy is considered a skill game and not gambling?

[Roulette Zeitung]

Why is rummy is considered a skill game and not gambling?

Because most players don't care about math.
Read this as an example (Gin Rummy - Game Strategy and Math): http://www.gamecolony.com/gin_rummy_game_strategy.shtml

Another example...
Another game...

In the past (i don't know in the moment if it is still availabe) online casinos with Boss Media software have had single deck Black Jack. If a player bet perfectly with a special basic strategy, he win for sure 0,15% of his bets without card counting or progressions.

You have to bet 10.000 to win 15. It's a safe bet, but the math with standard deviations will give you a bad surprise. Up to 6 months you can have a negative bankroll before the mathematical advantage works and the persistency was worthwhile.

Who can wait 6 months for a small advantage?

Leopold