Maybe not the entire time but a lot more time. I suppose you could define casual user as a non-geek who is not into 'puters as much as someone who made a living at it.Nothing else comes down with Libre Office or any other Open Source project. These people are volunteers from all over the world and they have nothing to sell, nor are they involved in any kind of trickery. It really is as simple and straightforward as that.
Edit: This "casual user" thing is starting to sound sillier all the time. What does going outside when the weather is nice have to do with it? In my career as a software engineer, I worked with people who had all manner of outdoor hobbies - one guy spent his vacations deep sea diving at spots around the world. Others owned cabins on lakes and spent weekends and summer vacations there. I could go on, but my point is that you lost me with that one. If you think that for a person to be something other than whatever "casual user" is, s/he must spend his or her entire time inside huddled in front of a computer, think again.