Online casinos like Treasure Mile are always looking for new ways to attract new customers to their sites. To achieve that, they might use a wide variety of tactics. For example, the might run billboard ads or sponsor a sports team.
Another method they use is giving these offers to welcome new players. These are generally only made to players who are registering a new account. You might be required to input a special code as you register, but these days, it's more common that the operators simply grant the offer to a new account by default.
If you're registering for a website that requires you to input a code for the welcome gift, it's usually not difficult to acquire one. In the past, these welcome codes were more exclusive, but those days are more or less over. Simply type in the name of the betting house and "bonus code" into Google and the majority of the time, you'll find one in the first results. Otherwise, you can find then on exclusive websites like ours, or even on the actual casino's promotions page.
It might grant you a number of benefits. Some of the more common ones are things like extra credits to spend at the casino or free spins to play on slots games.
New player promotions are a great way to experience exactly what a gambling site has to offer you. Sometimes, a welcome bonus might feature a specific game; for example, you might get free spins on a specific slots game. Other times, the gift might be broader (i.e. cash), allowing you to experience any game the casino has available.
At first glance, these promo offers come across as incredibly generous. In fact, you might think they're too good to be true. After all, what business in their right mind is going to give away hundreds of dollars? Almost all promotions are subject to terms and conditions, the most prevalent of which is the wagering requirement. This will often be something like 30x (try to choose bonuses with the lowest wagering requirements). In this case if you win $20 with your bonus, then you'll need to wager $600 worth of bets (i.e. 20 x 30) before you will be eligible to withdraw. Having said this, there may also be a bonus withdrawal cap of $200+- which is why these often aren't allowed or recommended for progressive jackpot slots.
The key to not ending up disappointed is to always read the terms and conditions. Once you've read them, it should become clear exactly how much of your own money you'll need to spend. In some cases, this might be quite a lot.
Some players like to just treat bonus spins and credits as the chance to "demo" an operator. It gives you the opportunity to try out all the games you're interested in and helps you to decide whether it's worth your time and money.