Now my question is, does it mean responsible gamblers never wasted their time and money when they are gambling? Then how about those losses that they have incurred, when they can use it to add to their emergency funds?
In order to become responsible gamblers they must have commited mistakes along the way like everyone else who got experienced in something. Therefore, they must have wasted their money and time until finally learning with their bad moves. However, if they are responsible gamblers right now, it means they aren't going to waste resources anymore like they did in previous times. Maybe in one or another gambling session they may surpass their personal limits a little bit, but nothing with real potential to damage their finances and personal life on long term.
What happens is that sometimes we are so stressed that we need an extra dosage of entertainment to relax and feel good. When that is the case, and when it happens sporadically, it can be positive for the gambler. It's just necessary to be careful to not turn this practice into a routine.