I was just billed 60$ worth of roaming. I was indeed in another country but I never turned on the roaming. I know for a fact because whenever I land in US or another country I get a text from fido about roaming but this time I never did.
When you said you never turned on the roaming, did you mean you enabled airplane mode? Most newer phones do not have a separate setting to enable/disable roaming. They do, however, usually have a separate roaming data setting. A phone with roaming data disabled, can still roam on other networks and use other services, but just not use data while roaming. The only way to prevent roaming now is to enable airplane mode or remove the SIM. If you enable airplane mode, you can still enable Wifi separately.
Your previous posts referred to Wifi-calling. Did you use that feature when you were abroad? Using Wifi-calling abroad is using your Fido services so you would get charged roaming fees (see here).
Hope this helps