Yes, I pick the hard puzzles on purpose. Under 30% success rate, or over 1000 seconds to solve.
Here I have another stuck puzzle:
I can eliminate all but clues 1, 7, and 8:
I cannot find any more complementary exclusion sets. Example: The line for $4.90 in the upper left box, and the "mocha" line in the bottom left box mean that "Mocha" is not $4.90.
I cannot find any more 2x2 sets. Example: Upper left box for money and men's names.
The daisy-chain for "Bryan < Caffe Latte < (+20 cents) Henry" does not intersect the relationship of "Austin < (+20cents) Fredrick". I've marked that neither Henry nor Bryan can have Caffe Latte, but that's the extent of the exclusions in these relationships.
I know the answer if I ignore logic and start playing "What If": If Fredrick is $4.80, then Eduardo is $4.70. Follow that through Toni and Iced Americano is $4.70. This leaves a violation of clue 8, because Henry is at $4.90 and Caffe Latte is $4.60.
Can this be done with logic alone?
If you want it, here's the puzzle with nothing marked: