Steak 'n Shake review: customer service/ drive through/ rudeness

Just went through a drive through experience with a steak and shake in bourbonnais IL. Not only did I sit at the speaker to place my order for a good 10 minutes I also sat in line for 30 minutes. During the time period of sitting in line my brother and myself (had a family outing mother was driving) had to use the restroom so we got out went into the establishment to try and use the restroom. Not only were we told that we couldnt use the restroom which after arguing with the manager for 5 minutes she ended up letting us use the restroom. After using the restroom I asked the manager why hasnt the drivethrough moved in 30 minutes. She tells me oh well I have a party of 30 and party of 20. now I understand having a party and all, but you dont have your drive through waiting in line for 30 mins and not have them moving. Not to mention the food wasnt even cooked fresh and was thrown together at the last second.