Facebook never disables an account for no reason and certainly not for the fun of it.
Facebook disables accounts that don't follow the Facebook Terms. Some examples include:
• Posting content that doesn't follow the Facebook Terms
• Using a fake name or not using your full real name.
• Impersonating someone
• Continuing behaviour that's not allowed on Facebook by violating the Community Standards
• Contacting other people for the purpose of harassment, advertising, promoting, dating or other conduct that's not allowed