One of the ones I hate most is Reddit, which actually has a pretty good web interface. The worst part about their app is I can't search for words in threads.
I'm actually on the other side of this - it's really easy to use their app to browse posts and read comments, where it's a bit more involved using the web interface.
My experience with Reddit mobile web has been frustrating, because every page has a secondary loading period that is entirely unnecessary and seems to only be loading styling and JS libraries. The old Reddit mobile (i.reddit.com, I believe) was fairly simple HTML (though to be fair, it didn't look good) that loaded quickly and felt responsive.
I browse the mobile reddit all the time and constant nagging to use the app was a real PITA until I discovered that I don't have to press the link to hide the "browse with the app overlay". You can simply scroll down and it will go away.