The new Greeks in the city received a lot of special privileges. They were allowed, for example, to sell their goods on the doorsteps of the Jew's stores. Since they were exempted from taxes and fees [and since] they didn't pay rent or have other expenses, they gave tough competition to the Jewish merchants. Even though the Jews didn't protest, even donating money for their relief, Venizelos complained that "the Jews did not welcome the refugees with open arms".
After the exchange of population with Turkey the composition of population in Thessaloniki changed dramatically. In 1926 80% of the population was Greek Orthodox and 15-20% Jewish. This event was the final blow for the Jewish community's influence in the economy of the city. The relationship between the Asia Minor Greeks and Jews was tense and the former seemed to have been more hostile towards the Jews than the older inhabitants of the city. Thessaloniki was a unique case for the Greek state because there the Jews were a majority. That is why special legislations were introduced by Venizelos in order to minimize the community's influence. On the other hand he also took measures to reduce any anti-Semitism that would be directed against the Jews, other measures to relieve the community from certain burdens and he reassured the Jews that they would be treated as equals. Of course, such moves had a purpose, and that was that Venizelos wanted to avoid any interference of "protector countries" - if he had a conflict free Thessaloniki, he also had a Greek Thessaloniki. Thus, the environment around the community was steadily becoming Hellenized and in a few years Thessaloniki will successfully be transformed to a modern Greek, Orthodox Christian city. The Jews accepted their new Greek citizenship but in the Lausanne treaty they were not mentioned as a minority - the treaty was mostly dealing with issues of Greek and Turkish minorities and trying to solve the problems between the two countries.
Measures that were against the Jews of the city however, must not be read solely as anti-Semitic (although in some cases they seem to have been) but as part of the bigger process of the nationalistic agenda of the modern Greek state that also had to deal with the wider problem of the region of Macedonia and a deeply complicated and difficult transition from an empire to a nation-state, from an Ottoman legislation to modern European model of administration.
quote from Fleming's book, "Greece: a Jewish history" by Yitzhak Immanuel