Just like the first comment already made everything clear to you @OP, yes exchanges actually do care about where your coins is coming from when it's deposited to their exchange. If your coins comes from a platform that they blacklisted such as mixer or casino, the exchange will definitely send you a notification asking to know the source of your assets or they will restrict your account and ask you answer their question concerning that deposit.
It happened to me once, the coin was withdrawn directly from mixer to my exchange wallet and they asked me to explain who sent the coins. They gave me a period of 7 days to respond else my account would have been suspended.
So what did you do after? Did you tell them? And why won't you anyway, right? Lol. For some, they might only lie if the the truth is that it came from illegal acts, or a known criminal have sent you that, in exchange of some works. We are lucky if we will get an exemption and we might be extra careful next time. This is why reading before using a service is also important, so that we won't get screwed, especially if we know to our selves that we are not 100 percent clean. I see that casino is also in the restricted list but actually, many casinos now requires a KYC. So it would be better if they can now give an exemption to the most of it.