1) Spontaneous meetings become impossible, scribbling something on a whiteboard becomes much more difficult, the barrier to communication is too high.
2) We've had bad experiences with people who work in other studios/HQ. They tend to shirk responsibility, and it's very frustrating to get them to actually acknowledge your issue as high priority. Managers assume this would carry into remote work if it were offered.
3) We work in R&D, all internet access is monitored/blocked and we use internal systems for communications only, so while we can VPN in sometimes it's discouraged because I have liberties at home that I don't have in my offices internal network.
They do their best to make a good office environment, but it's still open plan (much to my dismay, I can't ever focus in that environment for some reason) but try to strongly discourage remote working.