If you're referring to a travel router, one which you take from place to place, and connect it to the hotel or wifi cafe's AP, *that* wireless connection has to be established each time you visit that location. A router typically does NOT remember the places previously visited and use any saved SSID information (although I suppose it's possible, it *might* be a feature of some travel routers, you'd have to check the documentation). However, *your* SSID on that same travel router, the one your PC/laptop connects to, is going to remain the same (unless you decide to change it for some reason), and your PC/laptop will remember that SSID information.
IOW, we're talking about two different things here when it comes to SSID. The travel router's connection to the hotel or wifi cafe's AP, vs. the AP you've established on the router for your devices (PC/laptop). I was initially confused because I had assumed it was the latter that concerned you.