Do you think it is necessary to give tips or it is just a tradition that is required?
It's not actually required or necessary because in the first place it is your money that you bet and if you lose they don't give you cashback in real casinos and tipping them is like showing thanks for the profit you have earned from them.
Giving tips will always depend on their service and the profit that you have made, though sometimes Im not giving any tips even if I won simply because they didnt do anything to help me at all so I dont think they deserve to get it, if they are very helpful with you then this is the only time I will give a tip. This is not a requirement though, giving tip should always came from your own willingness and not just because someone forced you to do so.
I'm not really sure how the tipping culture started but basically, no one is required to tip someone whether they've supported and provided assistance to you or not. Tipping is just a courtesy to show thanks or something that is done willingly whether you want it or not. I guess it's pretty common for gambling operators such as card dealers, Slot operators, or even cashiers who exchange their cash for chips to receive tips from gamblers who won during their stay in the casino.
As for me, I rarely give tips during my stay on the casino as I rarely win anything from it, and I've already expected from the start since my main goal was to have fun. However, on rare occasions when I've hit some jackpots on the Slot game, I tip some of my winnings to those slot operators beside me as I feel that they are somehow responsible for my luck. But sometimes, there aren't any slot operators around so give tips to someone who's beside me or the cashier before exchanging my chips to cash.