Gambling isn't wrong when the user know his own limit. When due to over confidence or greediness crossing limits and going on debt for the purpose of gambling wrecks life. To me gambling is fun filled earning with the highest risk factor.
Considering gambling as fun filled earning, I think it's wrong. Soon, it will lead to something else, everything in this world moves and change, and mostly to improve or to climb to new level, so there is a chance that you'll still get addicted to gambling even if you are having fun doing it and putting a limit on your gambling.
If you make it a habit to gamble often, then you will surely be hooked. However, if you seldom gamble (like once or twice a year) and just for pure fun, then I don't think so that you'll get addicted to it.
Evertyhing in life when done often during the day, weeks, or months, will lead to a habit - hence, if you gamble almost everyday, you are building that habit and may be addicted to it. Now, if you play everyday, there will be two questions that you need to answer honestly: 1. do you gamble randomly or 2. do you gamble with a system you strictly follow? Answering this questions determines how gambling impact your life.