Active gambling while employed to do a job seems too much to justify, too much risk and too cheeky an action to ever justify if caught.
Doing active gambling like Slots, Dominoes, poker etc. that requires more focus while in the main job is not allowed.
It will instead interfere with those main jobs and just focus more on gambling.
Such employees lack loyalty and focus on the work they do, more concerned with what can actually be done elsewhere after work.
However if you gamble via lottery or entry type contests which is also a kind of gamble thats fair enough, any game or entry you can start and stop as the work requires or to answer the phone is fair. You are not using up much resources just filling out a form or similar kind of low level interaction during work, I've done that previously and its fine imo.
If you only do lottery or do football club betting, it can be done anywhere and anytime.
Just need to go in and determine how many bets to make and just have to wait for the outcome to happen.
It doesn't require more focus, so you can focus on the main work.
Based on the experience I have experienced, there is a friend of mine who is too focused on playing slots in the office and even neglects his own work.
Finally, some tasks that need to be completed are not on target.
This resulted in his position in the office not being good and getting a warning.