Only because your company owns the server. If they owned it and dropped POP3 in favor of web-based access it wouldn't really change too much other than you saying that you're getting the same benefit because the server is secure.

Unless you're using POP3 with SSL you're actually likely more exposed as pretty much every webmail implementation is SSL-encrypted. POP3 generally isn't and that means all your traffic is in open-text between your computer and the server - just like the majority of SMTP flow on the internet. Yours may be configured that way but it is certainly in a very small minority as such.

POP3 has a number of limitations that IMAP addressed for a client-server based email configuration. Webmail clients address some of these issues but not all of them. For me a combination of online and offline access is usually important so I like the ability to have a mix of the two.