- protecting your privacy from your local ISP, WiFi, school, government etc
- protecting your privacy from some forms of online tracking
- circumventing censorship
- circumventing geographical restrictions
If you combine masking of your IP address with a web browser that protects you from various types of browser-based fingerprinting, you are more in control of your privacy online. You get to decide, to a greater extent, who you share very personal information with. That doesn't seem very silly.
(disclosure: I'm one of the deeply silly cofounders of Mullvad)