Is this petty?

I stopped talking w/ this guy because he didn't offer my sister his seat. She was standing up eating and he didn't even offer her his seat. At least ask if she wants to sit down. He wasn't even eating. I thought it was rude, childish, inconsiderate and disrespectful. I'm 26 years of age and I'm single. December will make a whole year of me being single. I don't have time to play w/ a young minded ass man child. I pay so much attention to character so the slightest thing will turn me off. I want/need a gentleman. At this age I'm ready for a husband so I'm weeding out all of the bad seeds early. Would you ladies cut a guy off for that??