A couple of reasons:
-Lee has been solid all year with two complete games since moving over to Texas
-Weaver has been shaky lately. He is also 0-3 out of last 6 outings at Texas (0-6 as a team) with over a 6 era
-Texas has a fresh bullpen, only using one reliever for one inning yesterday
-Angels have gone through 4 different relievers in the past two days
-Texas is at home and a great home team
-Angels on their third straight road game, traveling from LA to NY then NY to TX within a 3 day span, and a below .500 road record
-The line is set that high for a reason ie. Vegas know what they are doing here
I think the line should be closer, but no way should the Angels be favored here