That you can scoop canisters directly from a planet surface with your spacecraft? You don't HAVE to have an SRV with you.
Well I didn't know till just now. I don't know if it's craft specific and you will scratch your shield of course, but I can in my Asp Explorer.
Nice to know.
N.B. It can get a bit messy if they are lying up against something, but it's possible to nudge them free by ramming them gently. Wouldn't you know.