That is why whenever a site share the bonus or any other offer, everyone should gain good knowledge about that site before restoration or opposite. Until good information about that site is available, there should not be deposit. Moreover, I agree with you in any such case, one should definitely deposit a small amount of deposit first time, if that site get scammed you will loss all the assets so the maximum caution should be taken in this case.
You are right. New casinos usually attract new customers by offering high rewards and interesting promotions that are, most of the time, too good to be true. Unfortunately, many gamblers get lured by those fake promises and deposit too much money in hope to get a huge reward. At the end, they don't get any thing and their money get stolen by the scam casino. Gamblers should be more cautious and wait for reviews from more experienced users before sending their money to unknown persons.
Well, most casino promotions are too good to be true actually so it's not new to anyone. Especially to a new casino who are trying to build their reputation. So you can't just decide a casino is suspicious or scam because of its promotions but for the past reviews it has. If it doesn't have review since its new, check their community in social media especially on this forum, if the representative is active promoting it here then it's safe to try at least a little deposit. Don't just barge and deposit a large amount in a new site. There are many incidents of a reputed casino become shitty because of its unfair terms, that's why become so wary trusting them especially a new one.