That's possible too, but the issue I was thinking of wasn't exactly reception - it's that GPS signals bounce off buildings and so it looks like you're somewhere

That's possible too, but the issue I was thinking of wasn't exactly reception - it's that GPS signals bounce off buildings and so it looks like you're somewhere else. Stronger reception might actually make that worse. Japan has local satellites to help with this (QZSS) and local cars may handle that better than global phones.