Eats Near Shoreline Ampitheatre
There is a bunch of stuff on Castro St. in downtown Mtn View. Taqueria La Bamba is highly regarded. There is an In N' Out burger near the Rengstorff off-ramp depending how not too fancy you are trying to be.
Taqueria La Bamba No. 2
152 Castro St, Mountain View, CA
1159 N Rengstorff Ave, Mountain View, CA
It's been a while since I've eaten in downtown Mountain View but there are plenty of decent restaurants there. La Fiesta, Amarin Thai, Hangen Szechuan, Fu Lam Mum (new, haven't been here), Amici's pizzeria, just to name a few. I went to a nice little Turkish(?) restaurant right on Castro a couple of years ago but unfortunately can't remember the name of it:-( Oh yes, DO NOT go to Spice Islands (Singaporean food)...average food with some of the worst service I have received anywhere.
Yes, Castro has many spots to explore and enjoy ... but I think you will get to the concert in a more relaxed and happy mood if you stay out of downtown MV. Every Saturday night it's crowded and slow -- for good reasons ... but not what you might want before the show.
I recommend Los Altos Taqueria, at the corner of Rengstorff and Old Middlefield Way. Authentic Jalisco-style food, aguas frescas, beers, Mexican sodas, fresh free chips and salsa.
My favorite Journey song is "Be Good To Yourself" and I think this suggestion fits. Hope you will agree.
Los Altos Taqueria
2105 Old Middlefield Way Ste E, Mountain View, CA 94043