That's a good point, you are right that it could be spoofed. In my case when I asked for a number, they said I couldn't call them back and they will call me later. The number on caller id was definitely not a number the real company used as I determined with an actual company representative. It may help in this way to identify a fraud, but yes it won't help to verify that it isn't a fraud just seeing a legitimate number.

From what I gathered, this scammer was attempting to gather enough information for an account takeover. I immediately closed the account with the company, they can fuck off for not having good security measures.