I didn't thought that this will be consider as a feature, well, for security purposes, it might work.
For this issue, browser's saved logins do the job for this issue. It can be used but having password manager is safest way.
I think it's weird to consider it as a feature, they should offer two version like what this forum have, before we login, they ask how many minutes we want to stay or always stay logged in.
I have never experienced a site that logging out after few minutes, I only experienced a site logging out after few days or weeks, but it's in centralized exchanges.
Even we can always log in whenever we get logging out, but it will not make the gamblers comfortable.