How IBS-friendly is the US and Canada?

I have IBS-D, pooping around 3-4x a day. I am from the Philippines and I'll be traveling to the US for the first time. I usually travel to Asian cities which are pretty IBS-friendly like Tokyo where there's a toilet in almost every train station and there is a train station almost everywhere.

I'll be traveling to Portland, Oregon and Vancouver, Canada next month and I've been so anxious thinking about where I'd poop if I needed to. Where do people usually go for public toilets? Gas stations?