Don't all guys treat their gfs like garbage in front of their friends?

I have my friends over friday nights and we just treat my girlfriend like garbage. She cooks for us and we insult her and her family while we play cards. We'll purposely spill food on the floor and make her pick it up. My friend threw a drink in her face last week and we all cracked up. I held my hands out like I was going to hug her and when she got close I spit in her face. Everyone enjoyed it and we all laughed for hours. This is a normal Friday night for us. We just punish her all night. Well one of her dumb friends is trying to convince her not to be with me any more. I know it's a tad extreme, but don't all guys treat their girlfriends like garbage in front of their friends? I'd hate to tell them to stop now, because abusing her is part of the reason we get together every week.