You guys just need to get a bucket lid opener to pry it open with. I like buckets as well. I frequently ferment with the lid sitting on top, not closed down all the way, and top crop yeast in the first 48-72 hours, skimming the braunhefe starting around 24 hours post pitch (for yeasts that are top cropping strains).That's weird...I don't have any trouble wiht the lids on mine. Must be a different brand.
Or you've just got powerful hands...
Or I've broken too many parts of my hands over the years and/or I'm doing it wrong. 8^(
The buckets I currently have use lids that look like paint bucket or 5 gallon drywall mud buckets. They seal well but are a bear to remove.
Lately I've been transferring when there's about 2-4 gravity points left (about 7-8 days post pitch) and letting it finish the rest of the way in the keg. Seems to work great and the beer stays fresher longer it seems. And no worries about the permeability of plastic.