Bitcoin is easily bought and deposited, but buying small amounts can have big fees depending on where you live. Also, some providers will close accounts or restrict them if sending directly to a gambling site, so you have to send to private wallet first and then from there to the site.
For someone buying a few hundred chips to play small stakes the chatbox is often the cheapest option. May not be for everyone but it works for a lot of regulars on the site.
I wouldn't recommend making purchases from the chat. How can you trust someone you don't even know? How will the deal be done? Do you send money first, and then you get the chips? What if the other person doesn't send you the chips after getting the payment? I know that PayPal has a chargeback system, but why go through the hassle in the first place?
A casino platform won't ban your account or confiscate your funds if you deposit using an exchange wallet, so if you use a centralized exchange to fund your casino account, SwC in this case, you shouldn't have any problems, and I say this from experience because I do that myself whenever I need to. I even withdrew funds from the platform to a centralized exchange, and never had any problems. However, if you don't feel safe withdrawing, don't do it, but depositing from an exchange should be okay and that's a better way to fund your account than buying chips from a random person in the chat.
Some people have reported having cashapp accounts frozen by sending chips directly to gambling sites, and there are people who have said it has happened to them on seals.
As far as purchasing from the chat, as I said, there are several trustworthy people in there. Normally you would send via Paypal or on of the cashapp type services and then get chips. Players such as pman, JamieGold and TheCaretaker sell chips there regularly and have never stiffed anyone.
Obviously there are scammers there too, and while the chat community can be somewhat 'raw' at times we try to warn noobs about them. Just gives people another option.