As I travel and ran into problems to subscribe to services which required me to switch my IP address just to access it, it's hard for me to disagree that VPN services are convenient. Yet when I see "VPN is a Must" I can't resist answering to say that a VPN is just a tool to connect distant networks. So without using a leased line, for 2 networks to be connected securely, VPN is the traditional way to access for example the local network of a company.

I think the most exciting things for privacy against digital surveillance networks like Tor, i2p, and probably others.

I think when using the WiFi of others the most important thing to do rather than connect to a VPN service is to shutdown all local services like samba or others which share data. When I was at the university, people using macbooks had a sharing service running by default (I guess) so I was listening music on their computers and could look at their holidays pictures.

That being said I use VPN services myself so my grain of salt: it is just connecting 2 networks together and I don't think that just changing our IP address is the best way to get privacy. For example users can be tracked with an account, cookies, fingerprint of the browser, etc.