This is the same reason why credit card skimming still works in the US (no chip + pin here).
I got a magstripe reader for a project and had some fun swiping various cards and seeing what was contained. My drivers license had the number and my address which was interesting. The only cards I came across that weren't obvious plain text were hotel keys.
I am still surprised there is no chip & pin in the US, plus now they're rolling out "insecure by design" RFID chips so you can steal from someone without having to touch them...
Even their ATMs are defective by design, they spit out the cash before the card so a LOT of people leave their cards behind at the ATM, when this issue was solved like 20 years ago in the UK by spitting out the card first and beeping until you took it.
I would have to say the last one is solved, but don't get me wrong, the rest is a joke in the US. My "fake" bitcoins are more secure than my USD in Wells Fargo.
I didn't get a writer since the project required only a reader (the cards were written elsewhere). Readers are pretty cheap, writers are surprisingly expensive.
The main things you have to look out for are coercivity and tracks. Magnetic stripe cards come in both high-coercivity and low-coercivity (HiCo and LoCo). This is a bigger issue if you're doing writing, I believe most readers are compatible with both. There are typically 3 tracks of data available, so you'll also want a reader (or writer!) that can access all three.
The model I got could be programmed through a Windows only utility and that seemed pretty standard, so at least make sure you have a virtual machine with Windows on it. You'll need to program it to tell how to interact (as a keyboard is easiest) and if you want to fiddle with the tracks.
I got a magstripe reader for a project and had some fun swiping various cards and seeing what was contained. My drivers license had the number and my address which was interesting. The only cards I came across that weren't obvious plain text were hotel keys.