Xfinity Mobile charges $300 per Gb when traveling international, is this a trap?

By default Xfinity Mobile charges at a rate of $0.3 per Mb which is equivalent to $300 per Gb, this really concerns me. I've chatted with an online live agent and was kept on being told Global travel pass is better and you should use it. My problem is I don't really need any of these but there might be cases where my kid accidentally turned on data roaming and I can see bills easily in $1000s.

The online chat agent also told me that it's not possible to retro-activate Global travel pass for past usage, so basically I'm [Edited: "Language"] to fall into this trap unless I'm willing to pay $10 per line per day, so for an international travel of one week it will be $280 for a family of 4.