The two sentences have to be read together. Consider this:
Sie suchen Alternativen. Ich auch.
In this case, the meaning is clear: the speaker affirms the plan of the addressed.
Now, by saying,
Sie suchen Alternativen. Ich den besten Weg.
the speaker offers an another option. "You look for alternatives, well, I'll look for the best route."
It's mangled by advertising stratagems, obviously; the quotation marks have no business of being there, and -- given that the same person says boths sentences -- you would say
Sie suchen Alternativen, ich (hingegen) den besten Weg.
Note that in this case, though, the two statements are not contradictory: the Deutsche Bahn persona offers help. This would be clearer:
Sie suchen Alternativen? Ich finde den besten Weg (für Sie)!
Note that I changed from (implicit) "suchen" to "finden" because that's clearly what is intended here. We want an app that finds stuff, not only searches for it.