As Andy says, people who sell stuff travel, or if they are managing groups in multiple locations.
By far the norm is not even to move all that much around your building, much less go to other countries.
Networking is an issue for quants, and it is good that you've spotted that the lack of it slows you down. I put out regular announcements of quant events to 80,000 people in my social network, and even if you don't revceive that, a bit of googling will find seminars on financial maths, programming, etc in any major city.
There are large numbers of conferences in this field, and ones related to it.
Plus you understand that you must always try to maintain and expand your skills through education.