I like being in a slip for a variety of reasons:
Easy to get on and off the boat for maintenance, loading heavy provisions (beer) etc.
There's a vibrant community on our docks, I know everyone around me and they help watch my boat in my absence.
In the summer I run a window AC unit through the forward hatch, I like having free water and electricity. Having a hose is great for scrubbing the boat down.
Easy access from boat to bathrooms, showers and pool as well as marina store
If I forget something in my car I don't have to row back.
More protected from waves etc. If you set the right dock lines and spring lines, you're going to be fine. This will never happen to my boat: