Making new friends and connections with other people. The more time you spend in one place, the greater the chance you can develop new friends (or possible romance?) with another person.
Taking a peek at the local lives. I have been invited to weddings, dinner and many other activities because of the connections I have made with locals
Learning the language. Especially if you decide to travel in an area that is not popular with tourists. Many times you will be required to know a few key words or sentences.
After spending my whole summer in one country. (75 days) I would say one thing I noticed was that I wasn’t as motivated to explore anytime the weather wasn’t perfect or if I simply didn’t ‘feel’ like trying something new that day. There was no sense of urgency for me to go out and see a place since I knew I would be in the country for awhile. There would be days where I would just stay in and watch movies or surf the web, something I would never do if I was ‘fast’ traveling.
Another downside is the original fascination and wonder of a new environment would slowly dissipate especially if I stayed in one city for awhile. The food isn’t as unique and the people aren’t as handsome or pretty as I originally thought. 😉
Finally, the biggest CON about slow traveling is finally saying goodbye to your favorite cafe or restaurant and for many of you the connections you made during your travels.