Ernie is a slap hitting guy with a good glove. These guys dont hit the lottery in arb. ARB for hitters generally rewards HRs, RBIs, hits, slg, ops etc. One thing playing in Ernie's favour is that he was an All-Star which counts in the players column of "special achievments" but that doesnt guarantee a massive raise either.
Sanchez might only hit 10 HRs this year, not exactly a standout baseball card.
Also, bear in mind we have to judge these new arb rewards based on the recent bumps in the minimum salary. They started their arb 1 cases with almost double the base salary of guys even 6 years ago. Thats a big factor to the actual $ they get now. I'd wager the % increases are roughly the same