Driving to a testing center and sitting in your car could easily use $3 in gas and more of your time. 7-11 is absolutely everywhere here, you don't understand the level of convenience.
I'm in my condo right now, I could go to a 7-11, come back and have my result all within 10 minutes for $3. But yeah car culture in America is great
There is a 7-11 within short walking distance of virtually everybody here in Bangkok. And free delivery too from 7-11 if you order more than 100 baht (around $3)
> If there even is public transportation to speak of
The public transportation here in Bangkok is amazing. It's clean, on time, and affordable