Sometimes, not always, but sometimes I think people invite themselves looking for any opportunity of fellowship with one another rather than an opportunity to use our stuff. Our perceptions are easily turned into reality for us but sometimes our perception is not accurate.
I too try not to invite myself to places/things. I feel it is rude. But there are times when I want to spend time with others that i will put an idea out there, such as getting together at their place or doing something they enjoy, so as to make it easier for them. It doesn't always work out.