I'm not saying the employer should subsidize it. Some employers might. If your employer provides that perk, it might make sense to use it. Similar to how if a restaurant provides free wifi it might make sense to use it.

I think the real way to be secure from MITMs is to use a device that you control the root CAs of. If you control the root CAs, you'll be safe no matter what network you're on. If you don't control the root CAs, you'll be vulnerable no matter what network you're on (but some networks will carry a higher likelihood of an attack).