That's what I said to be honest, having 1or 2 device is enough maybe 3 if you want more device to be used for a specific purpose. I have 3 devices likely - mobile phone, tablet and laptop (I rarely use this laptop for work purposes though) and they have different purposes on personal and daily use. Moreover, I regularly change password too on my accounts and keeping most of it offline without using my devices, like keeping notes then have it somewhere safe.
Someone has 2 devices for cellphones and laptops and uses them for different conditions, but using both on different devices on one account may not be prohibited because you access them legally so that there is no suspicion of detecting history on the account, you must increase the authentication security from email to avoid unexpected hacking problems from malware or phishing.
In short, you should be aware that there are phishing attempts which may steal your username and password by asking you to click on links. If you receive any email about promotions, then check if it comes from the legit gambling site source.
Accessing accounts from centralized gambling will not be easy compared to phishing for wallets, even though someone else has a user and password but he has to verify the code from the email, but we still have to be careful of phishing attacks and have to get used to verifying a valid address before accessing any account .