If Snyder wasnt batting in the 8 hole with the pitcher behind him, he would have about a .240 OBP. He is intentionally or unintentionally intentionally walked about 1/5 of the time he steps to the plate. Whenever teams pitch to him, he strikes out or pops up, think Eric Byrnes.
So a player with a .235 AVG would have a .240 OBP if he didn't hit 8th?
Snyder hit 7th for 166 ABs last year and put up a line of .259/.363/.524/.887.
Snyder only has 81 ABs. Both Molinas, Torrealba, Rodriguez, Suzuki, Barajas(.300 BA, Martin, Piersynski, Saltamacchia and others have lower OPS because they aren't getting free bases on intentional walks, they hit in the middle of the order. Not a good argument.
Barajas has 125 AB, 124 batting 8th. Career line of .244/.291/.412/.703
Benji Molina has 2(!) BB in 152 ABs. You think that's because he's hitting 4th?
Yadir Molina has a career line of .263/.318/.362/.681. This is what you want from Chris Snyder?
Sal is still only putting up a line of .252/.308/.405/.714 splitting time between hitting 8th and 9th.
Snyder's career line is .238/.335/.406/.741
While definitely a consideration that the pitcher would pitch around the 8th hitter, it would also mean that Snyder's .578 SLG this month (higher than every other middle of the order catcher you listed) is even more impressive considering the lack of quality pitches you are claiming he sees. Hardly K'ing or popping up when not walked.
The ability to get walks has been demonstrated to be a hitters skill. Snyder has displayed that skill for the vast majority of his minor and major league career. He leads all catchers with a 4.36 P/PA. There is skill in that stat.
I repeat I think your analysis is lacking and flawed. I'm not sure if it's that you're biased from watching him every day and not seeing what the ability and production of the average ML catcher or what. Snyder is easily a serviceable MLB catcher at this point in his career.