I just bring my own brick for such circumstances. It takes no effort for me to evaluate the security, and it’s more flexible than counting on built in USB ports.
I've long since taken to carrying a USB battery that can charge and provide power at the same time. It's more reliable for me than USB condoms, and, well, it's a battery, which is useful too.
That’s not been my experience, but I’m sure it’s hyper location/company specific.
As another commenter mentioned, I too carry a battery for longer trips, which is useful for charging devices when physically on the move and away from outlets. The model I chose from Anker can also top up a MBP, albeit slowly.