Because imgur is a piece of shit. So is photobucket.
Honestly, why do people still use this filth?
Photobucket and Imageshack are complete shit, but those are mostly used by people who are very new to the internet and don't know any better. There is literally no other excuse for it.
Imgur however is a pretty good image host, at least on the technical part. What ruins it is the leadership, and especially the community. Sometimes when I'm bored I just browse images on Imgur using the sidebar and read the comments, and the people use that site are reprehensible for the most part, and not just because of the 9gag level meme-ery.
Still no such browser extension for mobile browsers.
Install Firefox on your shitty device. You can install practically the same addons as for the desktop browser. Install uBlock Origin, instead of AdBlock, AdBlock is trash (any version of it), trust me.
No need to be an ass about it. I'm not talking shit about your PC, am I? And no, Firefox sucks on Android. If it was more similar to the desktop version, sure whatever, but it's not. I'll just stick with my default browser and open the image in a new tab instead.
Did you try Iron? It's like Chrome minus the obsessive Google tracking. https://www.srware.net/en/software.php
Why don't people on LL though just upload images to LL? The Lab has perfectly good servers, and no one here is going to arbitrarily block your content because they disagree with it.