Underlying "How deposit bonus works?" is one fact: a coin's price keeps moving while it sits in an account. A balance held in coins changes value even when no bet is placed. A win can shrink while it waits for withdrawal, and a losing session can look better or worse than it was. How a casino displays and converts a crypto balance decides how much of that movement reaches the player, and stablecoins remove most of it.
Casinos show crypto balances in one of two ways. Some keep the balance in the coin itself, so its value in everyday money rises and falls with the market. Others convert each deposit into a traditional currency on arrival and show that figure, which freezes the value until withdrawal converts it back. The account settings or the cashier page state which approach applies, and the difference decides who carries the price risk while funds lie idle.
Bonuses at crypto casinos are fixed either in the coin or in a traditional currency, and the difference shows over a long wagering period. A bonus counted in coins moves with the market, so its real value on the day it converts can differ widely from the day it was granted. Wagering targets and maximum bets follow the same unit. The bonus terms name the unit, often in a single line beneath the headline figure.
Every conversion uses a rate, and the casino's rate is rarely the market price. A small spread between the two works as a hidden fee, charged once at deposit and again at withdrawal when a balance is converted in both directions. Comparing the rate on the cashier page with a public price at the same moment shows its size. On frequent small deposits the spread can cost more than the network fees do.
A stablecoin is designed to hold a fixed value against ordinary money, so the balance keeps its everyday worth from one day to the next.
Coins kept there between sessions carry both price risk and account risk, so moving out what the next session does not need limits both.
Yes, when a balance is converted in both directions the casino's rate applies a second time, so the spread is charged twice.
Yes, a held coin can lose value. Its price keeps moving while it sits in an account, so a win may shrink before it is withdrawn.
Noting the coin amount and its value when it moved is the only reliable way to see how a period of play really went.