I, too, am a very huge Star Wars fan and I pride myself on my extensive research and knowledge on the series of films. Your question is great and one that I have been mulling around with for quite some time. But you’re in luck because I feel I have the absolute perfect answer.
Firstly, I have found out that this Dr. Evazan wasn’t always a criminal, that may sound obvious with the title “doctor” but I wanted to clear this up. Dr. Dre is not a doctor and neither is Dr. Seuss but I’m sure some folks out there may confuse them for doctors. But Evazan was actually an established and well-renowned dentist in the Star Wars galaxy. But after botching up one of the Emperor’s niece’s ion-braces, he was forced to turn outlaw and partnered up with Ponda Baba and have been ripping it up across the galaxy with bounty hunters hot on their tail ever since.
Which leads to Mos Eisley. As Obi-Wan states “You won’t find a more wretched hive of scum and villainy” the two criminals wanted in 12 systems are leisurely keeping cool in one of the most dangerous places in the galaxy. So why did they risk the trouble to harass Luke Skywalker when he seemingly did nothing to bother them? Well they wanted to rape him. Well, Ponda Baba did anyway. Baba was a notorious pedophile and serial rapist, a “sexual sadist” if you will. There’s no subtitles to what he utters to Luke in the cantina and thankfully Luke doesn’t understand him but he clearly states: “I want to f@¢! you until you bleed green!” Gruesome, I know. Dr. Evazan tries to warn Luke to stay away from his brutish and horny friend but Luke was too brash. Sure, Evazan says “he doesn’t like you” but he was just trying to scare off Luke in a more discreet way. Luckily for Luke, Obi-Wan interferes and puts the outlaws in their place.
Your picture pal,