Crito
The dialogue takes place in Socrates' prison cell, where he awaits execution. He is visited before dawn by his old friend Crito, who has made arrangements to smuggle Socrates out of prison to the safety of exile. Socrates seems quite willing to await his imminent execution, and so Crito presents as many arguments as he can in order to persuade Socrates to escape. On a practical level, Socrates' death will reflect badly on his friends--people will think they did nothing to try to save him. Also, Socrates should not worry about the risk or the financial cost to his friends; these they are willing to pay, and they have also arranged to find Socrates a pleasant life in exile. On a more ethical level, Crito presents two more pressing arguments: first, if he stayed, he would be aiding his enemies in wronging him unjustly, and would thus be acting unjustly himself; and second, that he would be abandoning his sons and leaving them without a father.
Sophist
In comparison, Socrates accepted no fee, instead professed a self-effacing posture, which he exemplified by Socratic questioning (i.e., the Socratic method, although Diogenes Laërtius wrote that Protagoras—a sophist—invented the "Socratic" method). His attitude towards the Sophists was by no means oppositional; in one dialogue Socrates even stated that the Sophists were better educators than he was, which he validated by sending one of his students to study under a sophist. W. K. C. Guthrie classified Socrates as a Sophist in his "History of Greek Philosophy".