I believe both behaviors violate the Terms of Service - it's generally frowned on to create multiple accounts to work around usage limits, and I know the TOS prohibited scripted interactions designed to maximize 24/7 usage (the subscriptions are very much based on the assumption that you will "be normal" about them)
And yet businesses seem to have no trouble paying for multiple accounts. I’m sure OP could register as a business or even recruit a friend to pay for an account on his behalf. I don’t think Anthropic cares as long as you’re paying them for the two accounts…
Business plans usually require a 5 seat minimum, charge per seat, and have different pricing levels - but yeah, nothing stops you from registering an LLC. Namecheap is even running a special: Buy a domain name and get an LLC for free: https://www.namecheap.com/apps/business-starter-kit/
(not affiliated, I was just very surprised when they tried to upsell me last time I renewed my domain :))