[lambda]

I ride a Brompton, and that is one of the big reasons; I can just take it inside, and stash it under my desk, rather than having to lock it up outside.

However, it is inconvenient in some situations. When I go to a bar, or restaurant, or movie theater, it's sometimes hard to find a place to put it that's out of the way. Since a lock is cumbersome and inconvenient, and I don't usually need it, that means I don't make a habit of carrying one, but then I'll hit a situation where it really would be more convenient to lock it up than take it in, but now I don't have that option.

That said, I do ride my Brompton as my daily commuter, and do bring it in with me, and most bars, restaurants, or the like do have enough room for me to stash it somewhere. But you do have to be willing to put up with people who think it's a little strange, or the people who joke "hey, I don't try to bring my car into the bar", and you do sometimes need to be creative to find a way to stash it securely and also out of people's way.